GAS TECHNICIAN 2
WORKBOOK
Appliance Technical Institute of Canada
FIRST EDITION
Gas Technician 2 Workbook
Table of Contents
1. Module 10
2. Module 11
3. Module 12
4. Module 13
5. Module 14
6. Module 15
7. Module 16
8. Module 17
9. Module 18
10. Module 19
11. Module 20
12. Module 21
13. Module 22
14. Module 23
15. Module 24
16. Gas Technician 2 Practical Handbook
17. Gas Orifice Capacity Chart
18. Gas Technician Practice Questions
© 2020 Appliance Technical Institute of Canada
Module 10
Advanced Piping and
Tubing Systems
© 2020 Appliance Technical Institute of Canada
UNI T 10
Unit 10 – Chapter 01 Code Requirements and Approved Joining Methods
Indicate true or false:
1.
A pressure test is performed after the appliance is installed.
A. True
B. False
Complete the following sentence:
2.
Before the appliances are connected, the system shall be pressure tested using ___________________.
A. Air or inert gas
B. Air or soap solution
C.
3.
Inert gas or soap solution
When would you perform a soap test?
A. After every service call
B. Any time the gas supply is turned on
C.
4.
When a leak is indicated by a drop in pressure
What must be done to piping or tubing passing through concrete?
A. It should be welded.
B. It should be painted yellow.
C.
5.
It must be sleeved, coated, or double-wrapped
May a sleeve installed in pavement to allow free movement of the pipe also serve as a vent pipe
inspection point?
A. Yes
B. No
6.
What colour is used to identify gas piping or tubing?
A. Red
B. Yellow
C.
Blue
D. Green
© 2020 Appliance Technical Institute of Canada
1
UNI T 10
7.
When identif ing piping or tubing with banding or labels marked gas or propane what is the
maximum identification interval permitted?
A. 20 ft
B. 25 ft
C.
30 ft
D. 35 ft
Complete the following sentence:
8.
A manual shut-off valve shall be of the ________________________, and certified for its intended purpose,
and it shall not be subjected to either a temperature or a pressure outside of its certified rating range.
A. Butterfly, eccentric, or ball type
B. Plug, ball, or eccentric type
C.
9.
Eccentric, plug, or butterfly type
How must multiple outlets that are installed in a laboratory (school or other) be protected from
leaking gas into the area accidentally?
A. A solenoid valve interlocked with a gas sensor.
B. By a sign in the classroom identifying gas is present in the room.
C.
A clearly marked, readily accessible, master shut-off valve.
10. What are the requirements for joints in steel piping used in gas systems?
A. Threaded, flanged or welded.
B. Compression fittings.
C.
Joints properly sealed with paint.
11. Which of the following is not an appropriate gasket material for gas applications?
A. Natural rubber
B. Neoprene
C.
Nitrile
© 2020 Appliance Technical Institute of Canada
2
UNI T 10
Unit 10 – Chapter 02 Welding Safety, Certification and Procedures
1.
Which of the following is not a major welding hazard to workers in the vicinity of welding
operations?
A. Ergonomic
B. Physical
C.
Chemical
D. Environmental
2.
What type of radiation do x-rays, and gamma rays produce?
A. Non-ionizing
B. Ionizing
3.
List the adverse effects from ultraviolet radiation produced by arc welding.
A. Hearing loss
B. Burns to eyes and skin from hot metal and sparks
C.
4.
Burns to eyes and skin from a reflection off bright objects
After welding is completed in an area where combustible material is present how long should a fire
watch be maintained
A. At least 30 minutes
B. 4 hours
C.
5.
24 hours
What type of protective glove should be worn when performing welding work?
A. Knitwrist-type
B. Slip-on-type
C.
Gauntlet-type
D. Safety cuff-type
Indicate True or False:
6.
Pants with cuffs should always be worn while performing welding work.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
3
UNI T 10
7.
What should you never do while working with oxygen and acetylene?
A. Keep oxy-acetylene equipment away from oil or grease
B. Use the cylinder in a vertical position
C.
Test for leaks using a soap test
D. Repair a faulty cylinder
8.
Is acetylene a very stable gas that is easily compressed to high pressures?
A. Yes
B. No
9.
What should be done if welding is taking place in a confined area?
A. Ensure adequate ventilation.
B. Wear a mask
C.
Wear gloves
10. Should oxygen and acetylene regulators be oiled regularly?
A. Yes
B. No
11. How many air changes per hour are required in a welding shop?
A. One
B. Two
C.
Three
D. Four
12. With what are oxygen and acetylene cylinders fitted to minimize the possibility of explosion in case
of fire?
A. Shut off valves
B. Fusible plugs
C.
Regulators
13. To what angle should pipe be beveled if it is to be welded?
A. Approximately 45°
B. Approximately 37 1/2°
C.
Approximately 22 1/2°
© 2020 Appliance Technical Institute of Canada
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UNI T 10
14. When the pipe and fittings are set up for welding, how wide is the root gap?
A. 1/16 inch to 1/8 inch
B. 1/8 inch to 1/4 inch
C.
3/8 inch to 1/2 inch
© 2020 Appliance Technical Institute of Canada
5
UNI T 10
Unit 10 – Chapter 03 Utility and Non-Utility Piping
Complete the following sentence:
1.
When plastic gas piping is used underground, a minimum ___________ copper wire is taped along the
piping for tracing purposes using a metal detector or radio signals.
A. 16 gauge
B. 14 gauge
C.
12 gauge
D. 10 gauge
2.
Who is responsible for piping downstream of a gas utility meter?
A. Fuel supplier
B. Installer
C.
3.
Property or building owner
Coatings on underground steel pipe are made of what material?
A. Fusion Bonded Epoxy
B. Coal Tar Enamel
C.
Polyethylene
D. Asphalt Enamel
4.
What colour are the coatings on underground steel pipe?
A. Green or yellow
B. Yellow or blue
C.
Blue or green
Indicate True or False:
5.
Most non-utility gas piping and tubing operate aboveground.
A. True
B. False
6.
Which of the following is not one of the three options for identifying gas piping or tubing?
A. The entire piping or tubing system shall be painted yellow
B. The piping or tubing system shall be provided with red banding
C.
The piping or tubing system shall be provided with yellow banding
D. The piping or tubing s stem shall be labelled or marked GAS or PROPANE
© 2020 Appliance Technical Institute of Canada
6
UNI T 10
Complete the following sentence:
7.
For supply piping systems carrying pressures _____________ and over, you must identify and label the
supply pressure in addition to the identification requirements in clause 6.17.1.
A. 2 psi
B. 4 psi
C.
6 psi
D. 8 psi
Indicate True or False:
8.
The CSA B149.1 Gas Code does not require the identification of gas piping in a residence
A. True
B. False
9.
What are the final blueprint drawings used to locate and identify piping called?
A. Ladder drawings
B. As-built drawing
C.
Installation drawings
10. What is the surest way to identify the contents of a sealed pipe?
A. Trace it back to its source
B. Tap on it
C.
X-ray it
© 2020 Appliance Technical Institute of Canada
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UNI T 10
Unit 10 – Chapter 04 Piping Layout, Drawings and Symbols
1.
If there is a discrepancy between the specifications and the drawings, which one is taken to be
correct?
A. Drawings
B. Specifications
2.
The manufacturer s installation and service manual are supplied with every appliance. How much of
it should you read?
A. Just the final startup and commissioning page
B. Should already know it
C.
3.
All of it
Do the installation and service manuals supplied by the manufacturer always specify details of
replacement parts?
A. Yes
B. No
4.
The two ways that manual valves are joined to the gas piping systems are:
A. Threaded or flanged
B. Flanged or soldered
C.
5.
Soldered or threaded
Which of the following is not a function of an automatic valve?
A. Control the firing of the burner
B. Open or energi e when the controller calls for the burner to ignite
C.
6.
Act as a safety shut-off valve
Describe the function of a solenoid valve.
A. Energize (open) on a call for heat and de-energize (close) when the heat demand is satisfied.
B. Control the burner without anyone being present
C.
Interlocks with a gas sensor to prevent gas leaks
© 2020 Appliance Technical Institute of Canada
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UNI T 10
Unit 10 – Chapter 05 Sizing High-pressure Piping and Tubing
Indicate True or False:
1.
The reasons for having separate sizing tables for natural gas and propane fuels are because of the
differing properties as gases.
A. True
B. False
2.
Match the procedural steps of pipe sizing with the order in which they should be performed.
A. Sketch the system:
B. Size pipe sections:
C. Select a table:
D. Prove the Code zone (if pressure is over 2 psi):
E. Determine the Code zone:
© 2020 Appliance Technical Institute of Canada
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UNI T 10
Figure 1
3.
What is the longest measure run for Figure 1?
A. 72 ft
B. 88 ft
C.
91 ft
D. 212 ft
4.
What is the LER for Figure 1?
A. 112.59 ft
B. 117.72
C.
120.34
D. 124.16
© 2020 Appliance Technical Institute of Canada
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UNI T 10
5.
For Figure 1, what is the correct size for pipe A?
A. ½ inch
B. ¾ inch
C.
7/8 inch
D. 1 ¼ inch
6.
For Figure 1, what is the correct size for pipe B?
A. ½ inch
B. ¾ inch
C.
1 inch
D. 1 ¼ inch
7.
For Figure 1, what is the correct size for pipe C?
A. 1 inch
B. 1 ¼ inch
C.
1½ inch
D. 2 inch
8.
For Figure 1, what is the correct size for pipe D?
A. 1 inch
B. 1 ¼ inch
C.
1½ inch
D. 2 inch
9.
For Figure 1, what is the correct size for pipe E?
A. 1 inch
B. 1 ¼ inch
C.
1½ inch
D. 2 inch
© 2020 Appliance Technical Institute of Canada
11
UNI T 10
Figure 2
10. What is the longest measure run for the low-pressure system in Figure 2?
A. 50 ft
B. 54 ft
C.
72 ft
D. 122 ft
11. What is the longest measure run for the high-pressure system in Figure 2?
A. 54 ft
B. 132 ft
C.
160 ft
D. 175 ft
12. What is the LER for Figure 2?
A. 175.01 ft
B. 176.73 ft
C.
180.18 ft
D. 200 ft
© 2020 Appliance Technical Institute of Canada
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UNI T 10
13. For Figure 2, what is the correct size for pipe A?
A. ½ inch
B. ¾ inch
C.
7/8 inch
D. 1 ¼ inch
14. For Figure 2, what is the correct size for pipe B?
A. 1 inch
B. 1 ¼ inch
C.
1½ inch
D. 2 inch
15. For Figure 2, what is the correct size for pipe C?
A. 1 inch
B. 1 ¼ inch
C.
1½ inch
D. 2 inch
16. For Figure 2, what is the correct size for pipe D?
A. 1 inch
B. 1 ¼ inch
C.
1½ inch
D. 2 inch
17. For Figure 2, what is the correct size for pipe E?
A. 3/8 inch
B. ½ inch
C.
7/8 inch
D. 1 inch
© 2020 Appliance Technical Institute of Canada
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UNI T 10
Figure 3
Schematic diagram of a two-stage propane piping system using copper tubing
18. What is the longest measure run for the low-pressure system in Figure 3?
A. 20 ft
B. 30ft
C.
35 ft
D. 80 ft
19. For Figure 3, what is the correct size for pipe A?
A. ½ inch
B. ¾ inch
C.
7/8 inch
D. 1 ¼ inch
20. For Figure 3, what is the correct size for pipe B?
A. ½ inch
B. ¾ inch
C.
7/8 inch
D. 1 1/8 inch
21. For Figure 3, what is the correct size for pipe C?
A. ½ inch
B. ¾ inch
C.
7/8 inch
D. 1 ¼ inch
© 2020 Appliance Technical Institute of Canada
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UNI T 10
22. What is the longest measure run for the high-pressure system in Figure 3?
A. 20 ft
B. 30ft
C.
50 ft
D. 80 ft
23. For Figure 3, what is the correct size for pipe D?
A. 3/8 inch
B. ½ inch
C.
¾ inch
D. 7/8 inch
© 2020 Appliance Technical Institute of Canada
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UNI T 10
Unit 10 – Chapter 06 Purging Operations on Large Piping Systems
1.
With what would you purge a pipe sized 4 inches or over, if it has been tested with air?
A. Carbon dioxide or nitrogen or a mixture of both
B. Nitrogen or Radon or a mixture of both
C.
2.
Radon or carbon dioxide or a mixture of both
What can occur when purging is not carried out correctly?
A. The wrong gas could enter the pipe.
B. There could be a blockage in the pipe that goes undetected.
C.
3.
The accidental explosion of a gas-air mixture outside and inside the pipe.
Is it acceptable to purge a new gas line through the burner system into a combustion chamber?
A. Yes, if the building is vacant
B. No
4.
Why is it important to purge the air out of larger diameter pipes with an inert gas prior to the fuel gas
being introduced into the pipe?
A. So there will be no air in the pipe to support combustion
B. To prevent the mercaptan from being washed out of the gas when introduced into the pipe for
the first time.
C.
5.
To ensure the gas will ignite properly when turned on for the first time.
What is an alternative to completely purging long, large pipes with nitrogen?
A. Air-purging
B. Slug-purging
C.
6.
Fuel gas to fuel gas purging
What is normal purge velocity for large pipes?
A. 100 ft/min
B. 150 ft/min
C.
200 ft/min
© 2020 Appliance Technical Institute of Canada
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UNI T 10
Unit 10 – Chapter 07 Rigging and Hoisting
1.
Where can you find the requirements for safe rigging work practices in Canada?
A. Provincial or Territorial OHS acts and regulations
B. B149.1 Natural gas and propane installation code
C.
2.
TSSA Guidelines
Which of the following describes an asymmetrical load?
A. An object with a high center of gravity due to the object's long shape and/or composition
B. An object with a low center of gravity due to the object's long shape and/or composition
C.
3.
An object with an off-center center of gravity due to the object's irregular shape and/or
composition
Which of the following describes a symmetrical load?
A. An object that, because of its uniform shape and composition, has its center of gravity located
exactly in its middle.
B. An object that, because of its odd shape and composition, has its center of gravity located off
center.
Choose the correct volume for the following rectangle/square:
4.
Concrete block, 9 feet long x 3 feet wide x 5 feet high
A. Block weight = 120 cu ft x 150 lbs./cu ft = 18,000 lbs.
B. Block weight = 130 cu ft x 150 lbs./cu ft = 19,500 lbs.
C.
5.
Block weight = 135 cu ft x 150 lbs./cu ft = 20,250 lbs.
While performing Pre-Use Inspection you discover the wire rope sling shows signs of localized wear,
abrasion or scraping. Is the sling safe to use and why?
A. Yes, as long as it appears to be strong enough to support the load - In order to stay on schedule
with the project.
B. No, it is not safe to use - Slings must be removed from service when any substandard conditions
exist.
6.
When a wire rope sling is used in a basket hitch, the diameter of the load where the sling contacts the
load can reduce sling capacity. What is the ratio used to determine the loss of strength or efficiency
and is referred to as?
A. D/d Ratio
B. R/d Ratio
C.
D/r Ratio
© 2020 Appliance Technical Institute of Canada
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UNI T 10
7.
Which type of sling can be used safely in explosive atmospheres?
A. Vinyl covered steel cable sling
B. Synthetic sling
C.
8.
Fabric sling
When using a chain for overhead lifting, what alloy grade or grade is recommended?
A. Either grade 50 or 100 is recommended
B. Any chain that is heavy steel.
C.
9.
Either grade 80 or 100 is recommended.
How often should hooks be inspected?
A. Before and after each use
B. Weekly
C.
Annually
D. Before and frequently during use
10. What should do if your inspection reveals a small gouge in the hook?
A. Remove from service
B. Inform your supervisor and use the hook
C.
Repair the gouge
D. Nothing a small gouge won t affect the hook
11. What are three common shackles used in rigging and hoisting operations?
A. Snap, wide body, and bolt type
B. Screw, wide body, and bolt type
C.
Wide body, screw, and snap type
D. Bolt, screw, and snap type
© 2020 Appliance Technical Institute of Canada
18
Answers
Unit 10 – Chapter 01 Code Requirements and Approved Joining Methods
1. B
2. A
3. C
4. C
5. A
6. B
7. A
8. B
9. C
10. A
11. A
Unit 10 – Chapter 02 Welding Safety, Certification and Procedures
1. A
2. B
3. C
4. A
5. C
6. B
7. D
8. B
9. A
10. B
11. D
12. B
13. B
14. A
Unit 10 – Chapter 03 Utility and Non-Utility Piping
1. A
2. C
3. C
4. B
5. A
6. B
7. A
8. B
9. B
10. A
Unit 10 – Chapter 04 Piping Layout, Drawings and Symbols
1. B
2. C
3. B
© 2020 Appliance Technical Institute of Canada
4. A
5. B
6. A
1
Unit 10 – Chapter 05 Sizing High-pressure Piping and Tubing
1. A
2. A – 1, B – 4, C – 2, D – 5, E – 3
3. C
4. C
5. B
6. C
7. D
8. B
9. D
10. B
11. B
12. C
13. D
14. C
15. D
16. D
17. B
18. B
19. C
20. A
21. C
22. C
23. A or D
Unit 10 – Chapter 06 Purging Operations on Large Piping Systems
1. A
2. C
3. B
4. A
5. B
6. C
Unit 10 – Chapter 07 Rigging and Hoisting
1. A
2. C
3. A
4. C
5. B
6. A
© 2020 Appliance Technical Institute of Canada
7. B
8. C
9. D
10. A
11. B
2
G2 Gas Technician Module 10
1.
0.5" w.c.
What is the Max
pressure drop
>7" w.c. NG
2.
1/2". Clause 6.3.9
Piping less then
Nps _____ shall
not be used in a
concealed
location.
3.
1. 3" in diameter
...
4.
1. High pressure test prior to connecting
appliance. Disconnect piping at gas
meter and before appliance valve train.
...
5.
1. Isolate the piping system
...
6.
1. Type of fuel
...
7.
1" w.c.
What is the Max
pressure drop 7"
- 14" w.c. NG
8.
2 1/2". Clause 6.9.2
Piping of NPS
_____ and over
shall have
welded pipe
joints
19.
4. Pressurize system
with air or inert gas to
specified test
pressure.
How do you do a High pressure
test
20.
5. Length of piping
...
21.
6. Total btu input for
each appliance
What must you know to size a
piping system.
22.
20 ft or less. Clause
6.17.1
How far must banding be spaced
for labeling an institutional
buildings gas line
23.
350 psi. Clause 6.2.9
Every hose and fitting shall have a
minimum working pressure of?
24.
After piping system is
installed and before
any appliance is
connected to it.
When do you do a high pressure
test?
25.
Annex H
Purging practices are located in
which Annex?
26.
ASTM A53. Clause 6.2.1
Piping shall comply with what
standard?
27.
Brazing
approved mechanical compression,
press connect, approved flare.
Clause 6.15.3,How is underground
tubing joined
28.
The break point
pointing on the same
side as the appliance
Manual shut off valves shall be
installed with?
29.
A flare joint
an approved fitting and a press
connect. Clause 6.9.9,A joint in
seamless copper, brass or steel
tubing shall be made by?
30.
It is certified to
CAN/ULC-S652. Clause
6.9.6
A joint sealant can be used if?
31.
Malleable steel and
iron. Clause 6.2.2
What type material(s) is a fitting
required to be when used with steel
pipe?
32.
Natural rubber. Clause
6.9.7
Gasket material cannot be made of
what material?
33.
No. Clause 6.20.1
Can you connect a hose to a
vented appliance?
9.
2. Cap or plug open ends
...
10.
2. Leak test with meter and appliance
connected under normal operating
pressure. Use a manometer or lowest
volume test dial on meter. 10 min
duration
...
11.
2. Max range shall exceed test pressure
by at least 15% but less then 300%
...
12.
2. Supply pressure
...
13.
3. Insert a pressure gauge at one end of
the system
...
14.
3. Leak test using a liquid solution under
normal operating pressure. Check all
fittings.
...
15.
3. Pressure gauge shall read in
increments of 2psig or 2% of maximum
dial reading of pressure gauge.
Whichever is less.
High pressure
test gauges
must be:
16.
3. Type of material
...
17.
4. Can also check system with
manometer in an existing system which
measure in. of W.C. this is for systems up
to 14" W.C.
Three tests
required by
code when
installing
34.
No. Clause 6.20.3
Can you extend a hose from one
room to anot her?
35.
No they cannot.
Clause 6.14.2
Can bushings be nested?
4. Pressure drop
...
36.
NPS 2 1/2 or greater.
What size piping requires welded
pipe joints?
18.
37.
Outdoor and
underground
services. Clause
6.2.16
Plastic piping or tubing shall only be
used for
38.
Outdoor use only.
What location can you install a #3.16
manual shut off valve?
39.
Plug
ball or eccentric type. Clause 6.18.1,A
manual shut off valve shall be of the
40.
Schedule 40.
Clause 6.2.3
Gas piping with operating pressure up
to and including 125 PSIG shall be at
least schedule?
41.
A stairwell within a
dwelling unit.
Clause 6.7.2(a)
Piping and tubing shall not be installed
in a stairwell other than
42.
Steel
copper, plastic clause 6.1.1,What
material should a piping and tubing
system be made of?
43.
Threaded
flanged, press connected, welded.
Clause 6.9.1,Joints in steel piping must
be:
44.
To allow expansion
contraction and vibration,Why do you
use a corrugated metal connector in a
commercial, industrial or process
application
45.
Tracer wire. Clause
6.15.14
When buried what will accompany
plastic piping and tubing
46.
True - provided
they are cleaned
inspected, tested and the equivalent of
new material. Clause 6.1.2,Piping,
tubing and fittings can be reused true
or false
47.
Type G
L, K. Clause 6.2.4,What type of Copper
tubing is used for gas system?
48.
Type L or G
externally coated
with extruded
polyethylene
or type K. Clause 6.2.7,Copper tubing
underground shall be either type:
49.
Welding
press connect, mechanical
compression. Clause 6.15.2,How is
underground piping joined
50.
The working pressure differential between the
gas meter outlet and the appliance regulator
inlet at furthest appliance from meter
Define
pressure
drop
Module 11
Pressure Regulators,
Overpressure
Protection, Meters, &
Fuel Containers
© 2020 Appliance Technical Institute of Canada
UNI T 11
Unit 11 – Chapter 01: Pressure regulators
1.
What is the restricting element of a regulator?
A. Spring
B. Valve disc
C. Diaphragm
D. Atmospheric vent
2.
What is the measuring element of a regulator?
A. Spring
B. Valve disc
C. Diaphragm
D. Atmospheric vent
3.
What is the loading element of a regulator?
A. Spring
B. Valve disc
C. Diaphragm
D. Atmospheric vent
4.
What would cause an appliance regulator to have too low of an outlet pressure?
A. Vent port plugged
B. Ruptured diaphragm
C. Sensing hole blocked
D. Inlet pressure too low
5.
The purpose of a gas pressure regulator is:
A. To keep the colour of the flame constant
B. To maintain even outlet heated air temperatures
C. To maintain a constant gas pressure at the gas valve inlet
D. To increase and maintain higher pressures as the load increases
6.
In a gas pressure regulator, the closing force is created by:
A. Decreased flow velocity
B. The inlet pressure to the regulator
C. The pressure under the diaphragm
D. The adjustable spring above the diaphragm
In a gas pressure regulator, the opening force is created by
A. Increased flow velocity
B. The inlet pressure to the regulator
C. The pressure under the diaphragm
D. The adjustable spring above the diaphragm
7.
8.
To increase downstream pressure of the regulator
A. The orifice size is changed
B. The adjusting screw is screwed out
C. The adjusting screw is screwed down
D. Replace the restricting disc and the spring
9.
What is the purpose of the regulator atmospheric vent?
A. Allow gas to escape
B. Sense downstream pressure
C. Allow the regulator to breath
D. Allow a connection for a secondary pilot
© 2020 Appliance Technical Institute of Canada
1
UNI T 11
10. A pressure regulator is said to be in equilibrium when the:
A. Opening force of the diaphragm is equal to the closing force of the orifice
B. Opening force of the diaphragm is equal to the closing force of the spring
C. Opening force of the spring is equal to the closing force of the upstream pressure
D. Opening force of the spring is equal to the closing force of the downstream pressure
11. What term describes the condition when the outlet pressure is lower than set point pressure during
flow conditions?
A. Rise
B. Boost
C. Droop
D. Lockup
12. If a regulator is installed backwards in a piping system, what is the most likely result?
A. The regulator will open completely
B. The regulator will close completely
C. Pressure downstream will rise above set point
D. No difference – they are non-directional valves
13. The purpose of a pitot tube in a regulator is to:
A. Provide mechanical advantage for positive shut-off
B. Relieve unwanted gases when overpressure occurs
C. Increase upstream pressure during static conditions
D. Keep downstream pressure closer to set point during flow conditions
14. The purpose of a pitot tube in a regulator is to:
A. Provide mechanical advantage for positive shut-off
B. Relieve unwanted gases when overpressure occurs
C. Increase upstream pressure during static conditions
D. Keep downstream pressure closer to set point during flow conditions
15. When flow rate increases through a regulator, what happens to the downstream pressure?
A. It increases
B. It decreases
C. It cycles/hunts
D. It stays the same
16. Identify part #2 in Figure 1.
A. Seal cap
B. Welch plug
C. Adjusting screw
D. Measuring element
17. Identify part #11 in Figure 1.
A. Stem and valve
B. Restricting element
C. Balancing diaphragm
D. Regulating diaphragm
Figure 1.
18. If a 5 psig line pressure regulator has a 3/4 inch vent tapping and the vent line must run 65 feet, what
must be done?
A. Use 3/4 inch pipe for the first 20 feet, then increase to 1 inch
B. Use 3/4 inch pipe for the first 50 feet, then increase to 1 inch
C. Use 3/4 inch pipe for the entire length – you may not change sizes
D. Use 1 inch pipe for the entire length – make the change at the vent tapping
© 2020 Appliance Technical Institute of Canada
2
UNI T 11
19. A line pressure regulator operating at 2 psig or less shall be exempt from the requirements of Clause
5.2.1.5 (B) when equipped with which of the following?
A. A vent leak-limiting system
B. An internal relief valve spring
C. A union on the downstream piping
D. A pitot tube and balancing diaphragm
20. Which category of gas pressure regulators are used to reduce the service line pressure to building
line pressure at the gas meter set?
A. Service regulators
B. Appliance regulators
C. First-stage regulators
D. Line pressure regulators
21. An undersized vent pipe on a regulator may cause the:
A. Pilot safety to fail
B. Restricting element to stay fully open
C. Restricting element to say fully closed
D. Regulator to go respond slow or sluggish
22. When the inlet supply pressure to a line pressure regulator exceeds 1/2 psig, it shall:
A. Be bypassed
B. Have a leak-limiting orifice
C. Be of a positive shut-off type
D. Have a valve located immediately downstream
23. What is the purpose of a reference tube connected to the combination gas valve regulator vent?
A. Supply the pilot gas flow
B. Activate the combustion fan pressure switch
C. Vent the upper diaphragm chamber into the combustion chamber
D. Enable the regulator to automatically adjust for pressure changes in the burner enclosure
24. What is “lockup pressure”?
A. The pressure downstream of a regulator under no flow conditions
B. The pressure downstream of a regulator under full flow conditions
C. The pressure downstream of a regulator during full relief conditions
D. The pressure downstream of a regulator which activates the internal relief valve
25. Where is the hydrostatic relief valve used?
A. Propane gas systems
B. Liquid propane systems
C. High pressure natural gas
D. Natural gas service meter sets
26. What is the maximum allowed propane pressure in a single-family dwelling?
A. 7” WC
B. 14” WC
C. 2 psig
D. 5 psig
27. A zero governor is designed to deliver gas at zero pressure in proportion to the suction pressure
created by mechanical air flow to a premix burner.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
3
UNI T 11
28. What type of regulator arrangement is required in all permanent propane installations?
A. Two stage regulation
B. Proportioning regulation
C. Zero governor regulation
D. Balance diagram regulation
29. Gas flow will be interrupted by changing a propane cylinder if an automatic changeover regulator is
used on the installation.
A. True
B. False
30. An air/gas proportioning regulator delivers gas under pressure in proportion to the pressure created
by mechanical air flow to a nozzle mix burner.
A. True
B. False
31. What units are usually used to express the rate of flow for a regulator?
A. SCFH
B. BTUH
C. MBH
D. KWH
You are selecting the line pressure regulator for a 2 psig natural gas system which had the
pipe sized for the maximum allowable pressure drop.
32. What operating inlet pressure would you use for the regulator capacity tables?
A. 0.5 psi
B. 1 psi
C. 1.5 psi
D. 2 psi
33. The arrow on a regulator body should point upstream.
A. True
B. False
34. When sizing a propane regulator system what determines the lowest expected vapour inlet
pressure?
A. Pipe size
B. Cylinder size
C. Regulator orifice size
D. Cylinder outside temperature
© 2020 Appliance Technical Institute of Canada
4
UNI T 11
Unit 11 – Chapter 02: Overpressure protection
1.
What is the maximum allowable pressure downstream of a pressure controlling device?
A. 2 psig
B. 5 psig
C. Lowest maximum pressure rating of any downstream components
D. Highest maximum pressure rating of any downstream components
2.
Of commonly used overprotection methods which gives the least obvious failure warning?
A. Pressure limiting
B. Automatic shut-off
C. Internal relief valve
D. External relief valves
3.
A relief valve will decrease a regulator’s capacity.
A. True
B. False
4.
What measures the system pressure when using a direct operated relief valve?
A. Pitot tube
B. Diaphragm
C. Loading spring
D. Restricting element
5.
What types of overpressure protection incorporate a restricting element?
A. Relief valves
B. Series regulation
C. Slam shut devices
D. Monitor regulation
6.
An overpressure shut-off (OPSO) will automatically reset.
A. True
B. False
7.
What would happen if a regulator vent became blocked while the regulator was in the open position?
A. Regulator would close
B. Regulator would remain open
C. Regulator would operate normally
D. Regulator setpoint would slowly drop
8.
Which type of pressure limiting system has a regulator that is rarely exercised?
A. Pilot system
B. Series Regulation
C. Working monitors
D. Wide open monitoring
9.
What are the minimum and maximum allowed set pressures for a line relief device installed on a 2
psi piping system?
A. Minimum of 2 psi and a maximum of 4 psi
B. Minimum of 3 psi and a maximum of 4 psi
C. Minimum of 4 psi and a maximum of 6 psi
D. Minimum of 6 psi and a maximum of 10 psi
© 2020 Appliance Technical Institute of Canada
5
UNI T 11
Unit 11 – Chapter 03: Meters
1.
What is the most common type of meter used on residential installations?
A. Geared
B. Lobed
C. Orifice
D. Diaphragm
2.
Which meter corrects for temperature and pressure?
A. Bellows
B. Mechanical Rotary
C. Electronic Volume Corrector
D. Electronic Temperature Compensating Index
3.
For what purpose does a gas fitter clock a meter?
A. Solely used as a gas leak check
B. To see how long it takes the test dial to go around
C. To determine how much gas an appliance consumes per hour
D. To check how much gas is consumed in a month for billing purpose
4.
When do you need to use a pressure correction factor when clocking an appliance?
A. Appliance input is over 400MBH
B. Meter pressure greater than 0.5 psig
C. Meter pressures greater than 2 psig
D. Meter pressures greater than 5psig
5.
If a natural gas meter with 7 inches water column pressure is used to clock an appliance and it takes
24 seconds for one revolution of a 2 cubic foot test dial, what is the input of the appliance being fired?
A. 300 MBH
B. 3,000 MBH
C. 30,000 MBH
D. 300,000 MBH
6.
If a natural gas meter at sea level with 5 psig pressure is used to clock an appliance and it takes 60
seconds for one revolution of a 5 cubic foot test dial, the CV of the gas is 1050btu/ft 3, what is the
input of the appliance being fired?
A. 315,000 Btu/h
B. 402,000 Btu/h
C. 422,100 Btu/h
D. 1,575,100 Btu/h
7.
An appliance is installed at a high elevation where the local atmospheric pressure is 85 kPa. If a
natural gas meter with 14 kPa (2psi) pressure is used to clock the appliance and it takes 30 seconds
for one revolution of a .05 m3 test dial, the CV of the gas is 10.35 kW/m3, what is the input of the
appliance being fired?
A. 60.67 kW
B. 62.10 kW
C. 70.79 kW
D. 83.21 kW
8.
Rotary meters are very effective for leak testing a gas system.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
6
UNI T 11
9.
What procedure should be used to identify if the test dial has possibly moved back to its original
position when conducting a working pressure leak test using a diaphragm meter?
A. Turn of the gas
B. Mark both test dials
C. Mark the position of the smallest test dial
D. Mark two positions on the smallest test dial
10. If the temperature of a gas trapped in a container is increased, what happens to the pressure?
A. Increases
B. Decrease
C. Stays the same
D. It depends on the type of gas
11. If the temperature of a gas decreases in a flexible container (such as the bellows of a diaphragm
meter), what happens to the volume?
A. Increases
B. Decrease
C. Stays the same
D. It depends on the type of gas
The image shows the display of a TCI indicating the temperature correct flow rate in m3/h of
natural gas. If the meter set pressure is 5 psi.
12. calculate the appliance input in Btu/h.
A.
B.
C.
D.
12,355 Btu/h
127,872 Btu/h
325,558 Btu/h
436,248 Btu/h
13. What is the temperature the gas heat values are based on?
A. -40°C
B. 0°C
C. 15°C
D. 32°C
© 2020 Appliance Technical Institute of Canada
7
UNI T 11
Unit 11 – Chapter 04: Fuel containers
1.
How long may a 100# propane cylinder be in use before it must be re-inspected and marked?
A. 1 year
B. 5 years
C. 10 years
D. 20 years
2.
The level of liquid propane in the cylinder has no effect on the vaporization rate.
A. True
B. False
3.
Assuming all of the propane cylinders are ¼ full which one will have the higher Btu/h vaporization
rate?
A. 20 #
B. 40 #
C. 200 #
D. 300#
4.
The largest cylinder that is made has a capacity of 1000 lbs of water. What is the maximum allowable
liquid propane capacity?
A. 300 #
B. 420 #
C. 500 #
D. 800#
5.
When calculating the effective load that an appliance will place on a propane container, which
formula should be used?
A. Effective load = Btu/h of input
B. Effective load = input load factor
C. Effective load = weight of propane load factor
D. Effective load = gallons of liquid propane 91,500
6.
Cylinders have a lower vaporization rate at higher humidity.
A. True
B. False
7.
When the demand of an appliance is too high for an average size container, what would be a practical
solution?
A. Install an excess flow valve
B. Install a propane vapourizer
C. Install multiple smaller appliances
D. Install an auto change over manifold
8.
What units of measurement are used to rate the fuel consumption of propane-fired stationary
engines?
A. Btu/h
B. kW
C. gal/hr
D. gpm
9.
What will happen to the vapour pressure in a cylinder when the temperature of liquid propane is
increased?
A. Not change
B. Increase
C. Decrease
D. Decrease only if the liquid content is 80%
© 2020 Appliance Technical Institute of Canada
8
UNI T 11
10. What surfaces on a propane storage container transfer heat and affect the vaporization rate?
A. The entire wetted surface of the container
B. The entire surface including the top and bottom
C. The entire surface not including the top or bottom
D. Only the surface that directly faces the sun and receives direct radiation
11. What is the pressure in the propane container is directly related to?
A. Temperature of the liquid propane
B. Temperature of the propane gas
C. Volume of propane left in the cylinder
D. Size of the propane container
12. What is indicated by a white fog or mist emitting from the liquid level gauge?
A. LP-gas is contaminated
B. Cylinder or tank is damaged
C. Liquid level gauge is defective
D. Maximum permitted filling level is reached
13. What is the relief valve setting of a propane cylinder?
A. 250 psig
B. 312 psig
C. 375 psig
D. 420 psig
14. What is the purpose of an excess flow valve?
A. Prevent liquid withdrawal from a tank
B. Prevent the tank from being filled too quickly
C. Prevent the tank from being over pressurized
D. Prevent excessive discharge of vapour or liquid
15. What is the purpose of a filler valve on a cylinder?
A. Used to fill a large stationary cylinder
B. Provide a large capacity relief opening
C. Act as a check valve to prevent excess flow
D. Prevent the cylinder or tank from rupturing
16. A shut-off valve cannot be installed upstream of a relief valve to allow for the removal of the relief
valve for servicing without emptying the contents of the tank.
A. True
B. False
17. If a leak occurs in the propane line between the first stage regulator and the second-stage regulator,
what is the first action that must be taken?
A. Close the excess flow valve
B. Open the fixed liquid level gauge
C. Shut off the propane container service valve
D. Decrease the pressure setting of the first stage regulator
18. If the relief valve on a refillable propane container opens, what is the first action that must be taken?
A. Close the excess flow valve
B. Open the fixed liquid level gauge
C. Shut off the propane container service valve
D. Cool the tank with cold water to decrease the pressure
© 2020 Appliance Technical Institute of Canada
9
Answers
Unit 11 – Chapter 01: Pressure regulators
1. B
2. C
3. A
4. D
5. C
6. C
7. D
8. C
9. B
10. D
11. C
12. B
13. D
14. A
15. B
16. C
17. C
18. D
19. A
20. A
21. D
22. C
23. D
24. A
25. B
26. C
27. A
28. A
29. B
30. A
31. C
32. A
33. B
34. D
Unit 11 – Chapter 02: Overpressure protection
1. C
2. A
3. B
4. B
5. A
6. B
7. B
8. D
9. C
Unit 11 – Chapter 03: Meters
1. D
2. C
3. C
4. B
5. A
6. C
7. A
© 2020 Appliance Technical Institute of Canada
8. B
9. B
10. A
11. A
12. D
13. C
1
Unit 11 – Chapter 04: Fuel containers
1. C
2. B
3. D
4. B
5. B
6. A
7. B
8. C
9. B
© 2020 Appliance Technical Institute of Canada
10. A
11. A
12. D
13. C
14. D
15. A
16. A
17. C
18. D
2
G2 Gas Technician Module 11 A
1.
At what pressure are correction
factors used when clocking the
meter?
When pressure
exceeds 1/2 psig
16.
What are the four
categories of a gas
pressure regulators?
First stage/Service Regulator,
Line Pressure Regulator,
Appliance Regulator
2.
Does an over-pressure shut-off
automatically reset?
No
17.
3.
Does a relief valve decrease a
regulator's capacity?
No
What are the four
elements of a directoperated regulator?
Loading Element, Measuring
Element, Restricting Element,
Atmospheric Vent
18.
How long may a 100lb propane
cylinder be in used before it must be
reinspected and marked?
10 Years
What are the test dials on
a meter used for?
To calculate the input rating of
an appliance, Leak in Gas pipe
19.
If a leak occurs in the propane line
between the first and second stage
regulator, what is the first action that
must be taken?
Shut off the valve at
the outlet of Tank
What are the two main
purposes of gas pressure
regulators?
To reduce and maintain the
downstream pressure and to
provide pressure to appliances
or burners
20.
The Loading Element
If an appliance rating plate is
missing, how can the input be
determined?
Manufacturers/
Orifice Size Table
What controls the
downstream pressure in a
regulator?
21.
If the relief valve on a refillable
propane container opens, what is the
first action that must be taken?
Apply cold water to
the container, it
reduces pressure
within the container.
What five factors need to
be considered before
selecting a regulator?
Rate of Flow, The Type of Gas,
Inlet Gas Pressure, Outlet Gas
Pressure and Pipe size
22.
What is lock up pressure
and how do you check it?
8.
If the smallest test dial moves during
a leak test using a meter, what does
this indicate?
Leak in the gas
piping system
downstream
The pressure under which
downstream pressure will
stabilize after burner shuts
down, Check it by closing shutoff valve and measure
downstream pressure
9.
If the temperature of a gas
decreases in a flexible container,
what happens to the volume?
It decreases
23.
Cylinders are Regulated by
Transport Canada, Tanks are
Boiler and Pressure Vessel Act
10.
If the temperature of a gas trapped
in a container is increased, what
happens to the pressure?
Increases
What is the defining
difference between
propane cylinders and
tanks?
24.
2.5 cu ft/hr
11.
If the type of system and the
pressure ranges safely handled by
the system are known, how should a
relief valve be chosen?
By Consulting
Manufacturers
Tables
What is the maximum
allowed leakage rate for
a leak limiter installed on
a natural gas regulator?
25.
1 cu ft/hr
12.
Name the three functions of a
diaphragm meter.
Consumption, Flow
Rate, Leak Test
What is the maximum
allowed leakage rate for
a leak limiter installed on
a propane regulator?
Name two types of displacement
meters.
Diaphram & Rotary
26.
What is the maximum
allowed propane
pressure in a building?
20 Psig
13.
14.
Should the arrow on a regulator
body point upstream?
No, It should face
the direction of flow,
downstream
27.
36''
15.
Under what conditions can a leak
limiter be used?
In the event the line
regulator doesn't
have an internal leak
limiter indoors.
What is the minimum
clearance allowed
between the vent
termination of a natural
gas regulator and a
building opening?
28.
What is the purpose of
the leak limiter?
To allow gas to escape if the
diaphram is ruptured
4.
5.
6.
7.
29.
What is the relief valve setting for a propane tank?
250 psig
30.
What is the relief valve setting of a propane cylinder?
375 psig
31.
What is the size of the largest Cylinder?
1000 Ibs W.C and 420 Ibs Propane
32.
What measures the system pressure when using a direct-operated relief valve?
Diaphram
33.
What must the size of the vent piping from a relief device be?
Same size as the opening
34.
What type of regulator arrangement is required in all permanent propane installations?
Two Stage Regulators
35.
What types of over-pressure protection incorporate a restricting element?
Direct operated Relief Valves,
Internal Relief Valves
36.
What would happen if a regulator vent became blocked with the regulator in the open
position?
Over pressure situation
37.
When flow rate increases through a regulator, what happens to the downstream pressure?
Increases
38.
Where is the hydro-static relief valve used?
Liquid Propane between two shut
off valves
39.
Where is the information on installation clearances for tanks and cylinders?
B149.2
40.
Which meter corrects for temperature and pressure?
Bellows
41.
Will gas flow be interrupted by changing a propane cylinder if an automatic changeover
regulator is used on the installation?
No
42.
Write the standard clocking formula for determining flow rate through a meter for gas
pressure less than 0.5 psig.
3600x0.5Sec (Time) X 1000
G2 Gas Technician Module 11 B
1.
8 things you must know
to select a gas regulator.
1. Type of gas
2. Max and min rate of flow
3. Max and min inlet pressure
4. Outlet pressure.
5. Range of adjustment
6. Size of pipe connection
7. Type of valve seat
8. Droop
Can you use a leak
limiting orifice on inside
regulators?
Yes
3.
An excess flow valve
allows liquid and vapour
to flow which way?
Both ways.
4.
How does a twin stage
regulator work and what
does it do?
Has two stages of pressure
regulation in one device. Reduces
tank pressure to supply pressure.
250 psig - 11" w.c.
5.
How do you mount a
disc limiting orifice?
Vertically mounted for proper
install
6.
How do you transport a
meter?
Upright
7.
How is a liquid
withdrawal valve
threaded?
Right handed
8.
How many times will
liquid propane expand
when released to
atmosphere?
270 times
9.
How much does one
pound of liquid propane
expand when converted
to vapour?
8.5 cubic feet
10.
How much do you fill a
propane tank?
80%
11.
How much pressure is
required to get a bellow
moving?
0.5" w.c.
How must meters be set
when installed?
Facing out from the wall with the
inlet and outlet connected to
supply and utility dealer piping
respectively
Incorrect lock up
pressure caused by a
plugged vent what to
do?
Clean or replace vent.
2.
12.
13.
14.
Incorrect lock up pressure
caused by cut valve seat or
worn out seat. How to fix?
Replace valve seat or
regulator
15.
Incorrect lock up pressure
caused by diaphragm rupture
how to fix?
Replace regulator
16.
Incorrect lock up pressure due
to regulator body being
twisted. How to fix?
Replace regulator
17.
In Ontario what type of
regulation must be used in all
permanent propane
installations?
Must have two-stage
regulation
18.
On a service regulator which
way do you turn the
adjustment screw to increase
pressure?
Turn clockwise to increase
pressure.
19.
Sluggish regulator action
caused by a stiff diaphragm.
Replace regulator
20.
Sluggish regulator action
caused by linkage friction
Replace regulator
21.
Symptoms of a sluggish
regulator?
Varying pressure or
pressure drop when burner
fires.
22.
Symptoms of incorrect lock
up pressure?
Pressure is to high, periodic
relief valve opening, and
periodic odour of gas near
vent area
23.
Types of gas meters?
1. Bellows
2. Rotary-type
3. Orifice-type
4. Turbine
24.
What 4 things must be down
when converting an appliance
from natural gas to liquid
petroleum?
1. Change orifice
2. Change spring
3. Adjust pressure
4. Label unit
25.
What are some uses of a gas
meter?
Measure consumption, test
for leaks, and to measure
input of an appliance.
26.
What are symptoms of
pressure drop at other burners
when main burner ignites?
No gas at other burners,
low fire at other burners,
and pilot goes out
27.
What are the 2 classifications
of propane containers?
Tank or cylinder
28.
What are the three
functions of a
regulator?
1. To reduce and maintain constant
downstream pressure
2. To allow pressure adjustments
to the appliance
3. To provide a smoother even
flow
29.
What are the three
operating forces of a
gas regulator?
1. Measuring element (diaphragm)
2. Restricting element (orifice)
3. Loading element (spring)
30.
What are three
functions of regulator
vents?
1. Allow for displacement of air
above measuring element so it
can operate.
2. Allows gas to escape incase of
diaphragm rupture or downstream
over pressure.
3. Can have leak limiting orifice
installed to allow for small
discharge in case of diaphragm
rupture
31.
What can a meter be
made of?
Tin, cast iron, pressed steel and
aluminium
32.
What can undercut pipe
threads cause in a
regulator?
May cause pipe to enter regulator
to far and block sensing passages
What does a cent
limiting orifice do?
What is the drill size?
How much gas per hour
will it allow to pass?
1. Allows airflow in and out of the
top of the regulator.
2. Normally #78 drill size.
3. Will allow one cubic foot per
hour gas to pass?(propane)
What does a first stage
regulator do?
Reduces tank pressure down to
service pressure. (Propane) 250
psig - 10 psig
What does a lock-off
type regulator do?
Where would it be
used?
Reduces pressure from lbs to lbs
or lbs to inches. Will lock off on
high or low pressure. Used where
relief vents are not permitted and
at gate stations.
33.
34.
35.
What does an appliance
regulator do?
Reduces supply pressure to
manifold pressure
What does a second
stage regulator do?
Reduces service pressure down to
supply line pressure. (Propane) 10
psig - 11" w.c.
38.
What does a service
regulator do?
Reduces service pressure down to
supply pressure.
39.
What does a single
stage regulator do?
Reduces tank pressure to supply
pressure through one orifice.
40.
What does the number
on a gas meter
indicate?
Indicates btu capcity
36.
37.
41.
What happens if a regulator
vent becomes blocked with
the regulator in an open
position?
Excessive downstream
pressure
42.
What is lock up pressure?
What should this not exceed?
1. The pressure under which
downstream pressure
stabilizes at when burner
shuts down.
2. Should not exceed
operating pressure by
more then 20%
43.
What is maximum first stage
pressure?
10 pisg
44.
What is the 3 governing rules
on discharge distance from a
relief valve on a propane
container?
1. 3 ft on a horizontal
plane from any building
open that is below the
relief valve
2. 10 feet on a horizontal
plane from an appliance
air intake or air moving
equipment
3. 10 feet horizontally from
any ignition source
45.
What is the closing force in a
regulator?
Downstream gas pressure
46.
What is the largest cylinder
manufactured?
1000 lbs
47.
What is the name of the
regulator that is found in a
combination gas valve?
Appliance regulator
48.
What is the purpose of a
temperature compensated gas
meter?
Allows them to work
outside at certain temp
ranges
49.
What is the purpose of purging
a propane cylinder?
To remove H2O
50.
What is the relief valve set at
for a propane cylinder?
375 psig
51.
What is the relief valve set at
for a propane tank?
250 psig
52.
What material can a vent line
for a pressure regulator
utilize?
Steel pipe, copper,
seamless aluminum or
steel tubing
Clause 5.5.1.a
53.
What meter does not require
lubrication?
Bellow meter
54.
What must a liquid withdrawal
valve be equipped with?
Must have an excess flow
valve
What must a relief
valve on a propane
cylinder be protected
with?
A rain cap
56.
What size should a
regulator vent line
be?
A size at least equal to the nominal
pipe size
Clause 5.5.1.b)
57.
What standards are
propane cylinders set
by?
Transport Canada
58.
What standards are
propane tanks set by?
Boiler and pressure vessel act
(ASME)
59.
What state is propane
in while under
pressure in a
container?
Both liquid and vapour
60.
What temperatures
must a propane
container never be
exposed to?
Temps greater than 125 F
61.
When does an excess
flow valve start
controlling the flow?
When it exceeds 1.5 times normal
flow
62.
When do you use a
surge limiting device?
How does it work?
Used when a regulator is required
to be slow opening. Uses a ball to
restrict the flow of air.
63.
When pressure of
propane changes what
also changes directly?
Temperature
64.
When should a
propane container not
be filled?
When it shows signs of damage,
deterioration or incorrect install
65.
Where is a liquid
withdrawal valve
installed?
Threaded into the bottom or
internally piped via a dip tube.
66.
Where is the system
regulator located?
Located between the service and
appliance regulator. Also known as
the low pressure regulator or zone
regulator
67.
Where must you never
store a propane
container?
Inside this applies to empty
containers as well
68.
Where should propane
cylinders be mounted
on a recreational
vehicle?
To the frame
55.
69.
Where would you install an
appliance regulator?
As close as possible to
the appliance
70.
Where would you not install a
regulator?
In a high heat zone
71.
Where would you use a bellow
type gas meter?
Domestic and
commercial installs
72.
Where would you use rotary
type gas meters?
Commercial and
industrial applications.
73.
Who tests propane cylinders?
Transport Canada
74.
Who tests propane tanks?
TSSA
Module 12
Basic Electricity for
Gas-Fired Equipment
© 2020 Appliance Technical Institute of Canada
UNI T 12
Unit 12 – Chapter 01: Power supply
1.
The electrical service supplied to a building is measured in what units?
A.
B.
C.
D.
2.
What does the electric meter record?
A.
B.
C.
D.
3.
Bonding
Jumping
Bridging
Grounding
What minimum size conductor is required to bond gas piping systems to the building s electrical
system grounding conductor?
A.
B.
C.
D.
7.
Push the button on the receptacle
Reset at the panel
Replace the fuse
Move handle off then back on
Permanently joining all non-current-carrying metal parts to ensure electrical continuity is a partial
definition of:
A.
B.
C.
D.
6.
Arc Breaker
Overcurrent device
Arc fault circuit interrupter
Ground fault circuit interrupter (GFCI)
Once a GFCI receptacle is tripped, how is it reset?
A.
B.
C.
D.
5.
Volts
Amperes
Horsepower
Kilowatt-hours
What device would protect users of electrical equipment from shock hazards in damp conditions?
A.
B.
C.
D.
4.
Ohms
Volts
Amperes
Horsepower
#4 AWG
#6 AWG
#8 AWG
#12 AWG
What is the most common device for the protection of electrical systems in residential applications?
A.
B.
C.
D.
Fuses
Transformers
GFCI receptacle
Circuit Breakers
© 2020 Appliance Technical Institute of Canada
1
UNI T 12
8.
Where would maximum ampacity values for overcurrent protection devices be specified?
A.
B.
C.
D.
9.
Motor
Appliance
Canadian Gas Code
Canadian Electrical Code
Overcurrent can occur when a motor starts up. What is the other most likely situation that causes
overcurrent?
A.
B.
C.
D.
Short circuit
Octopus effect
Overworking equipment
Worn out motor bearings
10. An electrical overload occurs very quickly.
A. True
B. False
11. What advantage do circuit breakers have over fuses?
A.
B.
C.
D.
They can be easily reset
They can be easily replaced
They have a lower failure rate than fuses
They can be temporarily bypassed by holding in the ON position
12. Wire is the most common form of electrical conductor?
A. True
B. False
13. A stranded wire has nearly the same current carrying capacity as a single solid wire of the same
gauge.
A. True
B. False
14. The maximum current rating of a No. 10 AWG conductor is less than that of a No. 14 AWG conductor.
A. True
B. False
15. For installations where steel studs and joists are used as framing members, what kind of cable must
be used?
A.
B.
C.
D.
BX
NMSC
NMD
SOW
© 2020 Appliance Technical Institute of Canada
2
UNI T 12
16. What is the interrupting capacity of a breaker?
A.
B.
C.
D.
Maximum amperage of the protected circuit
The amperage when the breaker begins to open
The amount of unbalanced current to break the circuit
The maximum supply amperage that the breaker is rated for.
17. Low-voltage circuits operate at what voltage?
A.
B.
C.
D.
1000mV or less
1 V to 30 V
30V to 250V
31 V to 750 V
18. What type of armoured cable should be used for installations subject to adverse service conditions?
A.
B.
C.
D.
AC
ACL
ACWU
TECH
© 2020 Appliance Technical Institute of Canada
3
UNI T 12
Unit 12 – Chapter 02: Interpret electrical drawings
1.
What is the purpose of ladder and schematic diagrams?
A.
B.
C.
D.
2.
How are components represented on connection diagrams?
A.
B.
C.
D.
3.
To show how circuits work and the function of their components.
To show were components are physically located
To show wiring identification and rating
To show how the wires are actually connected to component terminals
Simple pictorials
By labelled blocks
Dots
By symbols
Gas technicians/fitters should have a thorough understanding of electrical symbols. True or False?
A. True
B. False
4.
The sequence of operation of a circuit can be determined from what kind of drawing?
A.
B.
C.
D.
5.
What type of diagram is most helpful when trying to trace wires?
A.
B.
C.
D.
6.
Connection diagram
Block diagram
Ladder diagram
Pictorial diagram
In which operating position will the switches and other devices in a circuit be shown on a wiring
diagram drawn in the at rest state
A.
B.
C.
D.
7.
Connection diagram
Block diagram
Schematic diagram
Pictorial diagram
Open position
Closed position
Normal position
Energized position
What type of diagram does not show the return path for the circuits?
A.
B.
C.
D.
Connection diagram
Block diagram
Ladder diagram
Pictorial diagram
© 2020 Appliance Technical Institute of Canada
4
UNI T 12
8.
Control valves open and close in response to changes in temperature, pressure, humidity, or fluid
flow.
A. True
B. False
9.
A schematic diagram shows the electrical relationship between components in a circuit, while a
wiring diagram shows how components are actually wired.
A. True
B. False
10. Identify the following schematic symbol:
A.
B.
C.
D.
Heater
Thermopile
Transformer
Bimetallic strip
11. Identify the following schematic symbol:
A.
B.
C.
D.
Transformer
Heater
Thermopile
Bimetallic strip
12. Identify the following schematic symbol:
A.
B.
C.
D.
Normally closed temperature actuated switch
Normally open temperature actuated switch
Normally closed pressure actuated switch
Normally open pressure actuated switch
13. On a ladder diagram the source/hot line is drawn on the right.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
5
UNI T 12
Unit 12 – Chapter 03: Measuring and test instruments
1.
A multimeter incorporates which basic electrical meters?
A.
B.
C.
D.
2.
Voltmeter
Ammeter
Ohmmeter
All of the choices are correct
An ammeter is connected in parallel with the circuit under test.
A. True
B. False
3.
A continuity check is a measurement of what?
A.
B.
C.
D.
4.
Resistance
Voltage
Amperage
Capacitance
An ohmmeter should always be connected to a live circuit?
A. True
B. False
5.
What function should the DMM be set at when testing a furnace fan circuit?
A.
B.
C.
D.
6.
How many volts are in 250 mV?
A.
B.
C.
D.
7.
0.025 V
0.25 V
2.5 V
25
When the probes are touched together in a resistance test, what should the meter read?
A.
B.
C.
D.
8.
Voltage AC
Voltage DC
Amperage AC
Amperage DC
0
OL
Infinity
Nothing
How many ohms are in .
A.
B.
C.
D.
k
.
.
© 2020 Appliance Technical Institute of Canada
6
UNI T 12
9.
If you measure voltage across a switch in an energized circuit, what state is it in?
A. Open
B. Closed
10. If you measure the correct voltage across a load, such as a fan, but the load doesn t work, what is
wrong?
A.
B.
C.
D.
There is no power
There is no current
A switch is open
The load has failed
11. If one of the components in a series circuit is open, the voltage drop across the open component is:
A.
B.
C.
D.
Zero
Equal to the source voltage
Greater than the source voltage
A small percentage of the source voltage
12. Referencing the diagram shown here, what is the anticipated voltage reading at location B?
A.
B.
C.
D.
0 VAC
24 VAC
120 VAC
240 VAC
13. Ampere is also known as:
A.
B.
C.
D.
Power
Current
Resistance
Electromotive force
© 2020 Appliance Technical Institute of Canada
7
UNI T 12
14. Select the symbol for Alternating Current
A.
B.
C.
D.
15. Select the symbol for Direct Current
A.
B.
C.
D.
16. Select the symbol for Continuity Beeper
A.
B.
C.
D.
© 2020 Appliance Technical Institute of Canada
8
UNI T 12
Unit 12 – Chapter 04: Circuits and hardware
1.
How many hot wires are contained in the service conductors to a residential distribution panel?
A.
B.
C.
D.
2.
Where do branch circuits start?
A.
B.
C.
D.
3.
By the voltage supply
By the connected circuit breaker
By the amount of power the secondary windings can handle
By the ampacity of the supply conductors
All electrical connections shall be made where?
A.
B.
C.
D.
6.
Each receptacle
Each appliance
Each junction box
All choices are correct
How are transformers rated?
A.
B.
C.
D.
5.
At the wall switch
At the pole transformer
At the distribution panel
At the appliance transformer
All line voltage circuits have a continuous ground from the distribution panel to where?
A.
B.
C.
D.
4.
One
Two
Three
Four
In conduit
In outlet or junction boxes
In the appliance
In the distribution panel
Bonding conductors must be soldered.
A. True
B. False
7.
Switches are always located in the hot leg of a circuit.
A. True
B. False
8.
Switches must be in what position to conduct electrical current?
A. Open
B. Closed
© 2020 Appliance Technical Institute of Canada
9
UNI T 12
9.
Switches are operated by hand or by:
A.
B.
C.
D.
Pressure
Temperature
Fluid flow
All choice are correct
10. Despite their similarity in outward appearance to the contacts in a light switch, how are the contacts
in a toggle motor starter different?
A.
B.
C.
D.
They are current rated
They are horsepower-rated
They are located on the neutral leg
They have solder only wiring connections
11. Relays are magnetically operated according to which principle?
A.
B.
C.
D.
Microwave principle
Solenoid principle
Bernoulli s principle
Principles of plasma
12. Control relays are best suited for controlling single-phase pumps of any size. True or False?
A. True
B. False
13. How does a contactor differ from a relay?
A.
B.
C.
D.
It is magnetically operated
Contacts are rated for light duty
It can have multiple sets of contacts
Contacts are rated for large currents
14. What is meant by the term gangable box
A.
B.
C.
D.
Boxes that are used for switches only
Multiple boxes can be joined together
Boxes that are used for receptacles only
Octagonal type junction boxes designed for a large number of marrettes
15. Crimp-on connectors are convenient to use as they do not require any special tools.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
10
UNI T 12
Unit 12 – Chapter 05: Millivolt systems
1.
The point at which the two dissimilar metals are joined on a thermocouple is known as what?
A.
B.
C.
D.
2.
Thermocouples are used with which type of pilot?
A.
B.
C.
D.
3.
2 mV
8 mV
20 mV
30 mV
What does a thermocouple power when it is being heated?
A.
B.
C.
D.
6.
9 mV
17 mV
30 mV
250 or 750 mV
A thermocouple should be replaced if it cannot produce a closed circuit reading of more than.
A.
B.
C.
D.
5.
Direct Pilot
Standing pilot
Interrupted pilot
Intermittent pilot
What reading should an open circuit test on a thermocouple produce?
A.
B.
C.
D.
4.
Anode
Hot junction
Cold junction
Galvanic junction
Fan
Safety coil
Thermostat
Main gas valve
What portion of the hot junction should be heated by the pilot flame?
A. Full length of thermocouple
B.
away from the top
C. First .
to . thermocouple
D. Bottom Base
of thermocouple
7.
What should the temperature difference be between the hot and cold junctions?
A.
B.
C.
D.
8.
Maximum 250°F (120°C)
Maximum 400°F (204°C)
Minimum 400°F(204°C)
Minimum 750°F(399°C)
A thermopile contains approximately 10 to 30 thermocouples?
A. True
B. False
© 2020 Appliance Technical Institute of Canada
11
UNI T 12
9.
How are multiple thermocouples electrically connected within a thermopile?
A. Series
B. Parallel
10. What can cause to a very small, blue pilot flame?
A.
B.
C.
D.
Low gas pressure
Clogged pilot filter
Restricted pilot orifice
All choices are potential causes
11. An external power source is required for a control circuit operating on a thermopile millivoltage.
A. True
B. False
12. What type of current do thermocouples and thermopiles produce?
A.
B.
C.
D.
AC
DC
3-phase
Magnetic
13. A thermocouple must be under load to perform an open circuit test. True or False?
A. True
B. False
14. What does a closed-circuit test show?
A.
B.
C.
D.
Pilot stat dropout millivolts
Millivolt output not under load
Millivolt output unheated thermocouple
Millivolt maintained under load
15. During a pilotstat coil test at what mV reading should the coil drop out?
A.
B.
C.
D.
Between 2-1 mV
Between 5-2 mV
Between 20-15 mV
Between 30-15 mV
16. During a pilotstat coil test, at what point in time should the coil drop out?
A.
B.
C.
D.
After 3 minutes of the extinguished flame
After 90 seconds of the extinguished flame
Within 3 seconds of the extinguished flame
Within 90 seconds of the extinguished flame
17. When do manufacturers use750 mV powerpiles as opposed to 250 or 500mV?
A.
B.
C.
D.
When two millivolt circuits are powered
When AC power is required
When 3 phase power is required
When a circulating fan is powered
© 2020 Appliance Technical Institute of Canada
12
UNI T 12
18. Testing a 750 mV circuit is essentially the same as testing a 500 mV circuit, except for what?
A.
B.
C.
D.
Testing high limit
Testing pilotstat
Testing thermostat
Testing main gas valve
19. What is the voltage rating of a dedicated millivolt thermostat?
A.
B.
C.
D.
120 VAC
20 -30 VAC
0-1.5 VDC
250-750 VDC
20. Total electrical resistance in a control system includes the heat anticipator in the thermostat. True or
False?
A. True
B. False
21. The manufacturer recommends maximum lengths of wiring runs for self-powered control systems.
A. True
B. False
22. When troubleshooting the 750mV control circuit shown the following readings were taken. What is
the problem?
1 500 mV
2 0 mV
3 0 mV
4 0 mV
5 500 mV
A. Faulty thermostat
B. Faulty limit switch
C.
Broken coil in gas valve
D. Faulty thermostat wiring
© 2020 Appliance Technical Institute of Canada
13
UNI T 12
23. When troubleshooting the 750mV control circuit shown the following readings were taken. What is
the problem?
1 500 mV
2 500 mV
3 0 mV
4 0 mV
5 0
mV
A.
B.
C.
D.
Faulty thermostat
Faulty limit switch
Broken coil in gas valve
Faulty thermostat wiring
24. When troubleshooting the 750mV control circuit shown the following readings were taken. What is
the problem?
1
2
3
4
5
500 mV
0 mV
500 mV
0 mV
0 mV
A.
B.
C.
D.
Faulty thermostat
Faulty limit switch
Broken coil in gas valve
Faulty thermostat wiring
25. What is the recommended maximum length of wire, when using typical LVT No. 18 AWG, on a
millivolt system?
A.
B.
C.
D.
5 ft (1.5 m)
30 ft (9 m)
50 ft (15 m)
80 ft (24 m)
26. What is the maximum time allowed in the event of pilot outage for the thermocouple to cool down
and stop the flow of gas to the burner?
A.
B.
C.
D.
45 seconds
60 seconds
90 seconds
120 seconds
© 2020 Appliance Technical Institute of Canada
14
UNI T 12
Unit 12 – Chapter 06: Motors
1.
Where would you find the rated horsepower, the speed, full load amperage, and the date code of a
motor?
A.
B.
C.
D.
2.
What are the two main parts of an electric motor?
A.
B.
C.
D.
3.
DC electromagnetic rotor
Squirrel cage rotor
Start capacitor
External start resistor
This start relay has a normally open set of start winding contacts that are closed by the relay coil in
the run winding circuit. Once the motor is running the coil magnetic output is decreased and the
contacts are released
A.
B.
C.
D.
7.
AC or DC
Delta or wye
In phase or out of phase
Synchronized or asynchronized
What is the biggest difference in design between a synchronous motor and an induction motor?
A.
B.
C.
D.
6.
Wound rotor motor has insulated windings
Wound rotor motor has low starting torque
Squirrel cage induction motor has insulated windings
Squirrel cage induction motor has slip rings and brushes
What two ways can the stator phase coils in a three-phase induction motor be connected?
A.
B.
C.
D.
5.
Stator and rotor
Stator and capacitor
Rotor and capacitor
Capacitor and centrifugal switch
What is the difference between a wound rotor motor and squirrel cage induction motor?
A.
B.
C.
D.
4.
Frame
Housing
Armature
Nameplate
Motor starter
Current relay
Potential relay
Solid-state relay
This start relay has a normally closed set of start winding contacts that are opened by the relay coil
after the motor has started.
A.
B.
C.
D.
Motor starter
Current relay
Potential relay
Solid-state relay
© 2020 Appliance Technical Institute of Canada
15
UNI T 12
8.
This type of start relay uses transistors, diodes and triacs to break the start windings circuit at the
correct time.
A.
B.
C.
D.
9.
Motor starter
Current relay
Potential relay
Solid-state relay
When removing or replacing a capacitor, you should always short out the terminals to drain any
stored charge.
A. True
B. False
10. What is the purpose of an overload device?
A.
B.
C.
D.
To prevent motor slip
To prevent locked rotor
To synchronize the rotor
To protect the motor from overheating
11. What is the primary cause of motor insulation failure?
A.
B.
C.
D.
Motor slip
Locked rotor
Motor overheating
Unsynchronized rotor
12. From which vantage point is the motor's direction of rotation viewed?
A.
B.
C.
D.
From the top of the motor
From the drive end of motor
From either end of the motor
From the non-drive end of motor
13. What is the easiest way to tell if motor bearings require lubrication?
A.
B.
C.
D.
Rating plate
Specifications
Motor power supply
Look for grease fittings
14. How do you determine what wires are for which speed tap on a multispeed PSC direct drive motor?
A.
B.
C.
D.
Wiring schematic colour codes
Trial and error
Furnace specifications
Control board schematic
15. What best describes an ECM?
A.
B.
C.
D.
Split phase induction motor
A shaded pole induction motor
Permanent-split capacitor motor
A dc, three-phase motor with a permanent magnet rotor
© 2020 Appliance Technical Institute of Canada
16
Answers
Unit 12 – Chapter 01: Power supply
1. C
2. D
3. D
4. A
5. A
6. B
7. D
8. D
9. A
10. B
11. A
12. A
13. A
14. B
15. A
16. D
17. A
18. D
Unit 12 – Chapter 02: Interpret electrical drawings
1. A
2. D
3. A
4. C
5. A
6. C
7. B
8. A
9. A
10. C
11. B
12. A
13. B
Unit 12 – Chapter 03: Measuring and test instruments
1. D
2. B
3. A
4. B
5. A
6. B
7. A
8. C
9. A
10. D
11. B
12. A
13. B
14. A
15. B
16. B
Unit 12 – Chapter 04: Circuits and hardware
1. B
2. C
3. D
4. C
5. B
6. B
7. A
8. B
9. D
10. B
11. B
12. B
13. D
14. B
15. B
Unit 12 – Chapter 05: Millivolt systems
1. B
2. B
3. C
4. B
5. B
6. C
7. C
8. A
9. A
10. D
11. B
12. B
13. B
Unit 12 – Chapter 06: Motors
1. D
2. A
3. A
4. B
5. A
6. B
7. C
8. D
9. A
10. D
11. C
12. B
13. D
14. A
15. D
14. D
15. B
16. D
17. A
18. B
19. C
20. A
21. A
22. B
23. C
24. D
25. B
26. C
G2 Gas Technician Module 12
1.
3.41 btu
1 watt equals how many btu?
21.
Ground
What symbol is this?
2.
4 - two hot
one neutral, one ground.,How man
wires are contained in a residential
service conductor?
22.
Ground Fault Circuit
Interrupter (GFCI)
A _________ would protect you
from electrical shock near a
pool heater.
3.
15 amps
What is the maximum size fuse for 14
gauge wire
23.
In parallel
How do you measure volts
24.
In series
How do you measure amps
4.
20 amps
What is the maximum size fuse for 12
gauge wire?
25.
Isolate the device and
read in series
How do you measure
resistance?
5.
30 amps
What is the maximum size fuse for 10
gauge wire?
26.
It may overheat the wire
and cause a fire.
What could happen if a circuit
is fused higher then allowed?
6.
240v
single phase, 60 hz. 240/1/60. 100
amps,What are the standards for a
residential distribution panel?
27.
Limit Switch - Normally
Closed
What type of switch is this?
7.
AC Source
What symbol is this?
28.
Limit Switch - Normally
Open
What type of switch is this?
8.
Amperage
How to measure electrical service
supplied to a building?
29.
Liquid Level Switch Normally Closed
What type of switch is this?
9.
Amperage (amps)
The amount of electrical current that
will move through one ohm of
resistance when a force of one volt
is applied.
30.
Liquid Tight Conduit
Unsheathed conductors run
outdoors must be in....
31.
Liquid tight conduit
Unsheathed conductors run
outdoors must be in a?
32.
Monthly
How often should you test a
GFCI?
33.
Must be run in steel stud
or steel hoist applications.
When must you use BX cable?
34.
NMD (Non Metallic Dry)
What conductor can be used
in locations not exposed to
moisture?
35.
Ohms
Electrical resistance
measurement
36.
Only in locations not
exposed to moisture.
Where can you use NMD (non
metallic dry) wire?
10.
11.
12.
Can be used in damp
locations
Where can you use NMW (non
metallic wet) wire?
Circuit conductors
Fuses and circuit protect the ______ in
an electrical distribution system.
Closed
Safety controls are normally in the
_________ position.
A conductor which
connects the noncurrent carrying
parts of electrical
equipment
raceways or enclosures to the
service equipment or system ground
conductor.,What is a bonding
conductor?
14.
Contact
What symbol is this?
15.
Diode
What symbol is this?
37.
On the front
Where do you reset the GFCI
16.
Double pole
Single Throw,What type of switch is
this?
38.
Open
Operating controls are
normally in the _________ position.
17.
Double Pole Double
Throw
What type of switch is this?
39.
P=ExI
How do you calculate
wattage.
18.
An electrical meter
a main switch disconnect, a
distribution panel, fuses or circuit
breakers and wire conductors.,What
does an electrical distribution panel
consist of?
40.
A permanent and
continuous conductive
path to the earth
What is a grounding
conductor?
41.
Power or Control Fuse
What symbol is this?
42.
Pressure Switch - Normally
Open
What type of switch is this?
43.
Resistance decreases
What happens as the diameter
of a conductor increases?
13.
19.
electromagnetism
The operating principle of a motor is
based on?
20.
Flow Switch Normally Open
What type of switch is this?
44.
The resistance increases.
What happens when
the length of a
conductor increases?
62.
Transformer
What symbol is this?
63.
Two hot wires and one neutral for
240 v. 120 v has 1 hot wire and one
neutral.
Single phase wiring.
45.
Resistor
What symbol is this?
46.
The same way as the coil that
operates it.
How do you
designate a relay on
a schematic diagram.
64.
Volt
The unit of potential
difference or
electromotive force.
47.
Senses a minute leakage of
amperage to ground
5 milliamps,How
does a GFCI work?
65.
Volt-amps (VA) (E x I)
How do you rate a
transformer?
48.
Shows how the circuit works and
what the components do.
Ladder or Schematic
Diagrams
66.
Watertight BX cable.
What is TEK?
67.
Watt (p)
49.
Shows where the wires or
components are physically located.
Pictoral Diagrams
How do you measure
electrical power.
68.
Wet locations
50.
Shows where wires are connected.
Used for initial wiring or tracing
wiring.
Connection
Diagrams
Where must you use a
GFCI?
51.
Single pole
Single Throw,What
type of switch is
this?
52.
Single pole
Double Throw,What
type of switch is
this?
53.
Solenoid/Gas Valve
What symbol is this?
54.
Source
path, controllers,
loads and
fuses/circuit
breakers,What are
the components of
an electrical circuit?
55.
Temperature Actuated Switch Normally Closed
What type of switch
is this?
56.
Thermister
What symbol is this?
57.
Thermocouple
What symbol is this?
58.
They are heavier and can handle
larger amounts of current.
What are the benefits
of contractors over
relays?
59.
They can be solid or stranded
What can
conductors(wire) be
made of?
60.
They protect circuit conductors
What is the purpose
of breakers and
fuses?
61.
Three live wires and a ground. 208
or 575volts used in commercial and
industrial applications. Has higher
starting torque and lower amperage
than single phase.
Three phase wiring
Module 13
Fundamentals of
Controls
© 2020 Appliance Technical Institute of Canada
UNI T 13
Unit 13 – Chapter 01: Fundamentals of controls
1. The temperature disc, bimetallic strip and rod and tube controls all operate on which principle?
A. Electro-magnetism
B. Thermoelectric effect
C. Thermal expansion of solids
D. Thermal expansion of liquids
2. Sealed bellows controls operate on which principle?
A. Electro-magnetism
B. Thermoelectric effect
C. Thermal expansion of solids
D. Thermal expansion of liquids
3. Mercury is used in capillary tubes suitable for high temperature operation.
A. True
B. False
4. Solenoids operate on which principle?
A. Electro-magnetism
B. Thermoelectric effect
C. Thermal expansion of solids
D. Thermal expansion of liquids
5. Thermocouples and thermopiles operate on which principle?
A. Electro-magnetism
B. Thermoelectric effect
C. Thermal expansion of solids
D. Thermal expansion of liquids
6. What control components produce electricity when heated?
A. Transistor
B. Thermistor
C. Thermocouple
D. Bimetallic strip
© 2020 Appliance Technical Institute of Canada
1
UNI T 13
7. Solid state electronic devices are made up of electro-mechanical components that move.
A. True
B. False
8. A semiconductor device used to switch or amplify signals.
A. Diode
B. Transistor
C. Thermistor
D. Thermocouple
9. A semiconductor device used to allow the flow of current in only one direction.
A. Diode
B. Transistor
C. Thermistor
D. Thermocouple
10. A semiconductor device that changes its electrical resistance with a change in temperature.
A. Diode
B. Transistor
C. Thermistor
D. Thermocouple
11. A thyristor is different from a transistor in that it only needs a pulse signal to make it conducting
and thereafter, it remains conducting.
A. True
B. False
12. SCR, TRIAC, and DIAC are all what types of electronic devices?
A. Diode
B. Thyristor
C. Transistor
D. Thermistor
13. Thermostat, operating aquastat and operating pressuretrol all belong to what section of the
control system?
A. Operating controllers
B. Ignition control module
C. Limit and safety controllers
D. Combustion safety controller
© 2020 Appliance Technical Institute of Canada
2
UNI T 13
14. Low-water cutoff, gas-pressure switch, flow switch, all belong to what section of the control
system?
A. Operating controllers
B. Ignition control module
C. Limit and safety controllers
D. Combustion safety controller
15. Position and location are important factors for thermostat installation.
A. True
B. False
16. Thermostats should be placed in a room on an outside wall.
A. True
B. False
17. What is an operating aquastat?
A. It is a normally closed switch, that shuts off the gas supply when the temperature setpoint is
reached
B. It is a normally open switch, that shuts of the gas supply when the temperature setpoint is
reached
C. It is a normally closed switch, that turns on the gas supply when the temperature setpoint is
reached
D. It is a normally open switch, that turns on the gas supply when the temperature setpoint is
reached
18. What is the purpose of an operating pressuretrol?
A. To stop the boiler if the steam pressure gets too high
B. To start the boiler when the steam pressure drops
C. To shut-off gas supply in the event of an overpressure condition in the burner valve train
assembly
D. To shut-off gas supply in the event of an under pressure condition in the burner valve train
assembly
19. A thermocouple is considered a combustion safety control.
A. True
B. False
20. Select the combustion safety controls that work on the principle of flame ionization.
A. Thermopile
B. Infrared flame sensor
C. Ultraviolet flame sensor
D. Flame rectifier (flame rod)
© 2020 Appliance Technical Institute of Canada
3
UNI T 13
21. What device is used to sense combustion air or flue gas flow on any appliance that incorporates a
fan or blower?
A. Flow switch
B. Pressuretrol
C. Gas pressure switch
D. Air proving switch
22. Non-integrated ignition control modules designed for intermittent pilot, direct spark, or hot surface
ignition will also manage all of the other appliance activities such as humidistat, electronic filters,
heating pumps or fans.
A. True
B. False
23. On what type of gas appliance would a rod and Tube (Unitrol) valve typically be installed?
A. Gas range
B. Gas boiler
C. Gas Furnace
D. Gas water heater
24. How is the field wiring identified on a wiring schematic for an IFC?
A. Solid lines
B. Highlighted
C. Dotted lines
D. Solid Bold lines
25. What is a DIP switch?
A. Direct ignition proving sensor
B. An air flow differential pressure switch
C. A double pole double throw automatic switch
D. A manual electric switch that is packaged with others in a group
26. Pilot operated solenoid valves use pressure differential to assist the plunger in opening and
closing the main valve.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
4
UNI T 13
27. The servo regulator built into a combination gas valve serves as which type of gas pressure
regulator?
A. System regulator
B. Service regulator
C. Appliance regulator
D. Over pressure protection regulator
28. What is the name of the backup safety designed to shut off the burner if the temperature of the
water in the heater exceeds 2000 F?
A. T&P
B. ECO
C. Pilotstat
D. Aquastat
29. What feature acts as extra protection on a redundant gas valve?
A. On-off switch
B. Pilot adjustment
C. Servo regulator
D. A second automatic shutoff valve
30. How do electronic thermostat control temperature swing overshoot?
A. Night setback
B. Millivolt anticipator
C. Cycles per hour method
D. Adjustable Heat anticipator
31. What CPH setting do most electronic thermostats come pre-set at?
A. 1-2
B. 4-5
C. 7-8
D. 10-11
32. Different types of multi-stage thermostats use a variety of methods to initiate furnace staging,
select the method that employs algorithms to anticipate demand.
A. CPH staging
B. Setpoint staging
C. Time-based staging
D. Rate-of-change staging
© 2020 Appliance Technical Institute of Canada
5
UNI T 13
33. How can multiple wireless temperature sensors that use short range protocols such as Z-Wave
and Zigbee achieve a longer range?
A. Hard wire
B. AC adapters
C. Mesh network
D. Signal boosters
34. A 10K he
i
ha a efe e ce e i a ce f 10K
a
ha e
ea
e.
A. -550C
B. 00C
C. 250C
D. 1500C
35. A PTC thermistor will decrease its resistance with a temperature increase.
A. True
B. False
36. One advantage of a smart valve is that it uses a regular 110 VAC HIS.
A. True
B. False
37. How have redundant gas valves been adapted to give them modulating operation?
A. WiFi-enabled
B. Servo regulated
C. Electric Stepper motor
D. Electro hydraulic actuator
38. On an electric oven safety valve, the HSI must warm up sufficiently before enough electricity can
pass to open the gas valve.
A. True
B. False
39. A seismic valve will reset automatically once the vibration stops.
A. True
B. False
40. Cable release fire suppression gas valves can only be activated manually.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
6
UNI T 13
Unit 13 – Chapter 02: Control circuits
1. The left-hand side of the ladder diagram represents the incoming voltage.
A. True
B. False
2. Which electrical drawing would be considered a map of an electrical circuit?
A. Block diagram
B. Ladder diagram
C. Wiring diagram
D. Pictorial diagram
3. Which electrical drawing is best used to determine how current flows through the various parts of
the circuit?
A. Block diagram
B. Schematic diagram
C. Wiring diagram
D. Pictorial diagram
4. A schematic diagram is also known as a _____________________.
A. P&C drawing
B. Ladder diagram
C. Component layout
D. Connection diagram
5. What are the most common auxiliary devices found in control systems?
A. Relays
B. Switches
C. Contactors
D. Protective devices
© 2020 Appliance Technical Institute of Canada
7
UNI T 13
6. For this relay connected to a 120 Volts circuit, what is the full load amp rating for the normally
closed contacts?
A. 8 amps
B. 8.9 amps
C. 13.68 amps
D. 82.8 amps
7. Integrated electronic control boards have replaced most time delay relays.
A. True
B. False
8. These sine waves represent primary and secondary transformer circuit that are in phase.
A. True
B. False
9. For AC circuits, the difference between the hot, neutral wire to ground wire is described as what?
A. Phasing
B. Modulation
C. Sequencing
D. Polarization
10. What is matching the polarity of the primary and secondary sides of a transformer called?
A. Phasing
B. Modulating
C. Sequencing
D. Polarization
© 2020 Appliance Technical Institute of Canada
8
UNI T 13
11. What voltage reading should you get between the 120 VAC hot and ungrounded side of the
secondary, when checking for transformer phasing?
A. 24 VAC
B. 96 VAC
C. 120 VAC
D. 144 VAC
12. What is the purpose of the control modules safe start check?
A. To confirm the pilot flame
B. To confirm the main flame
C. To confirm the induced fan is running
D. To confirm there is not already an existing flame
13. What is the operation of a flame rollout switch
A. NC switch that opens on flame roll out
B. NO switch that breaks on flame roll out
C. NO switch that closed when the induced fan runs
D. NC switch that closed when the induced fan stops
14. You can determine the sequence of operation for all components connected to an IFC from the
wiring diagrams.
A. True
B. False
15. U e he DIP able h
configuration shown.
he e
i e
e he HEAT OFF DELAY e i g f
he DIP
i ch
A. 0 SEC
B. 60 SEC
C. 100 SEC
D. 180 SEC
© 2020 Appliance Technical Institute of Canada
9
UNI T 13
Unit 13 – Chapter 03: Servicing and troubleshooting circuits and components
1. The troubleshooting procedure is broken down into a series of specific steps. What should be
your first step?
A. Make a trial run
B. Test conclusions
C. Know the system
D. Replace the components
2. Suppose that upon testing a furnace, the fan motor will not run. The burner is operating, the heat
exchanger temperature is above the fan-on setpoint and the fan switch contacts are open. What
should you do?
A. Replace the fan
B. Replace transformer
C. Replace the fan switch
D. Replace the thermostat
3. S
e he f ace
ligh , he
across the thermostat connections.
a i calli g f
hea a d
ge a eadi g f 24 V
A. Replace transformer
B. Replace the gas valve
C. Replace the fan switch
D. Replace the thermostat
4. List Thermostats are an example of a control that can be recalibrated or readjusted.
A. True
B. False
5. What setting should the multimeter be on when testing the flame sensing circuit?
A. µAmps DC
B. µVolts AC
C. µAmps AC
D. µVolts DC
6. All IFC will have a fault code retrieval push button on the module.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
10
UNI T 13
7. Illustration 1 is a wiring drawing of a forced warm-air furnace using an intermittent pilot system
(Honeywell S86 control module). An electrical meter is shown with the test leads in a position to
check the voltage in the junction box. There are also lettered boxes with lines where you would
place the meter test leads to test components. Match the letter to the proper description of the
test being performed.
A. Check power supply voltage to control module
B. Check power at transformer secondary
C. Check for power to pilot valve
D. Check for open thermostat contacts
E. Check flame current
F. Check for power to main valve
Illustration 1 – Intermittent pilot control module with combination igniter-sensor and
redundant gas valve
© 2020 Appliance Technical Institute of Canada
11
UNI T 13
8. Illustration 2 is a wiring drawing of a forced warm-air furnace using a direct spark ignition system
(Honeywell S87 DSI module). ). An electrical meter is shown with the test leads in a position to
check the voltage in the junction box. There are also lettered boxes with lines where you would
place the meter test leads to test components. Match the letter to the proper description of the
test being performed.
A. Check power supply to control module
B. Check power at transformer secondary
C. Check for power to main valve
D. Check for open thermostat contacts
E. Check flame current
Illustration 2 – Direct spark ignition with combination igniter-sensor
© 2020 Appliance Technical Institute of Canada
12
UNI T 13
9. Illustration 3 is a wiring drawing of a forced warm-air furnace using a hot surface igniter
(Honeywell S89/890 control module) with a combination igniter-sensor. ). An electrical meter is
shown with the test leads in a position to check the voltage in the junction box. There are also
lettered boxes with lines where you would place the meter test leads to test components. Match
the letter to the proper description of the test being performed.
A. Check S89 terminals for power to the hot surface igniter
B. Check power at transformer secondary
C. Check S89 terminals for power to redundant gas valve
D. Check for open thermostat contacts
E. Check power supply to control module
Illustration 3 – Hot surface ignition with combination igniter sensor
© 2020 Appliance Technical Institute of Canada
13
UNI T 13
10. Using the fault code table in Illustration 4, what component, and its connections, should be tested
if the IFC red light is flashing one short flash following by one long flash?
A. Ignitor
B. Blower
C. Gas valve
D. Flame sensor
Illustration 4 – IFC fault code table
© 2020 Appliance Technical Institute of Canada
14
Answers
Unit 13 – Chapter 01: Fundamentals of controls
1. C
2. D
3. A
4. A
5. B
6. C
7. B
8. B
9. A
10. C
11. A
12. B
13. A
14. C
15. A
16. B
17. A
18. A
19. A
20. D
21. D
22. B
23. D
24. C
25. D
26. A
27. C
28. B
29. D
30. C
31. B
32. D
33. C
34. C
35. B
36. B
37. C
38. A
39. B
40. B
Unit 13 – Chapter 02: Control circuits
1. A
2. C
3. B
4. B
5. B
6. C
7. A
8. B
9. A
10. A
11. B
12. D
13. A
14. B
15. D
Unit 13 – Chapter 03: Servicing and troubleshooting circuits and components
1. C
2. C
3. D
4. A
5. A
6. B
7. A – b, B – a, C – d, D – c, E – f, F – e
8. A – b, B – a, C – d, D – c, E – e
9. A – e, B – a, C – d, D – c, E – b
10. C
G2 Gas Technician Module 13
1.
...
Flame failure
response time?
2.
...
2xπxFxL=
inductance
reactance
3.
...
4. Prove pilot or
main gas flame
22.
Closed circuit
test(thermostat CLOSED)
on a thermopile system.
400-450 milivolts
23.
Closed circuit
test(thermostat OPEN) on
a thermopile system.
600 milivolts
24.
Combination gas valves
have what in line with each
other?
Pilot gas valve in line with the
main gas valve
25.
Direct spark ignition-
Flame failure response 0.8
seconds
26.
direct spark ignition and
hot surface ignition,Types
of ignition control
modules?
intermittent pilot
4.
...
3. Energize the
main gas valve
5.
...
2. Ignite flame
6.
...
1. Safe start check
7.
...
Trial for ignition
time?
8.
...
Trial for ignition 4
seconds
27.
Wavy blue flame
Potential pre purge
time?
Excessive draft causes
what at the pilot location?
28.
Formula for capacitive
reactance?
C = capacitance
29.
Formula for capcitance in
parallel?
Ct = C1 + C2 + C3
30.
Formula for inductive
reactance?
L = inductance of cool in
Henries
31.
How are capactiors rated?
Capaciity (micro farads) and
voltage
32.
How are the contact
switches different on a
potential relay vs a current
relay?
Potential relays are normally
closed and current relays are
normally open.
33.
How can you increase
back emf?
Greater number of windings
across the stator
34.
How does a pilotstat
energize?
By the thermocouple
milivoltage
35.
How does a solenoid valve
work?
When energized it creates an
electromagnet that provides
opening and closing for the
valve.
9.
...
10.
...
Distance for spark
gap?
11.
...
Trial for ignition
safety lockout
range?
12.
...
What is flame
failure response
time?
13.
...
Spark gap 1/8 to
3/16"
14.
...
Flame failure
response 0.8
seconds
15.
...
Total for ignition
lockout between 15
& 90s
16.
...
F = frequency
17.
...
F = frequency of ac
voltage
18.
...
1/(2 x π x F x C) =
capacitive
reactance
19.
Another name for stator?
Field winding
20.
automatic gas valve, main gas and
pilot regulators,What does a
combination gas valve include?
Pilotstat
21.
away from drafts and within the pilot
flame about 3/8" to 1/2",Pilot flame
installation rules.
Must no impinge
on main burner or
heat exchanger
36.
How does a
Thermocouple
work?
Two dissimilar metals that are joined
at two junctions. Heating one of the
junctions produces a DC voltage. The
temp difference between the hot and
cold metals determines the quantity
of the DC voltage.
47.
it is in opposition of the
opposing fields causing
it to rotate.,What causes
the rotor to rotate?
A stator induces a counter
magnetic field
48.
it should be tightened a
1/4 turn past finger
tight.,Where do you
screw in a
thermocouple and how
tight should it be?
The thermocouple is screwed into
the pilostat coil
37.
How does the start
winding get
removed?
A centrifugal switch mounted on the
motor shaft will open at 85% of rated
speed taking the start winding out of
circuit.
38.
How far should a
flame rod project
into the flame?
1/2"
49.
Maximum operating
pressure of a steam
boiler?
15 psi
39.
How high can back
emf be compared to
line voltage?
2 1/2 times
50.
Most ignition control
modules flame failure
time?
0.8s
40.
How many milivolts
can a Thermopile
generate? What is
unique about this
system?
It can generate 750 milivolts and it is
sufficient to operate a milivolt gas
valve system. This system does not
require power.
51.
Motor speed formla.
RPM = (Hertz x 120)/# of poles
52.
Dirty
How should you size
a flame rod? Why?
Must have 4 times less surface area
then the ground. Normal practice is 10
times smaller. This causes the signal
to flow easier from the flame rod to
ground.
old or incorrect oil,
Over-tightened belts
and improper alignment
of the drive,Three
causes of bearing
failure.
53.
Pilot flame
rectification-
Pre purge up to 45 seconds
54.
The process of
conducting electricity
through a flame is?
Flame ionization
55.
Safety precautions
when handling a
capacitor.
They can hold an electrical
charge for a long period. To
prevent injury and equipment
damage bleed the charge across
the terminals with an
appropriately sized resistor.
56.
Sequence of operation
of an ignition control
module?
5. Monitor flame during cycle
57.
sufficient to hold a
solenoid like a pilot stat
energized.,How much
voltage will a
thermocouple produce?
It produces 25 - 30 millivolts
58.
Thermocouple milivolts
in a closed circuit what
is a good range?
10-15 milivolts
59.
Thermocouple milivolts
in a open circuit what is
a good range?
20-30 milivolts
41.
If you need to
replace a capacitor
what would you do?
what else can you
do if the best option
is unavailable?
Replace the capacitor with same
capacity and voltage. If that is not an
option Run capacitors +/- 10% and
start capacitors withing 10-35 micro
farads
Ina purely resistive
circuit what happens
to the current and
voltage?
They are in phase with each other
In capacitance which
one is the leader
current or voltage?
Current leads voltage
45.
In inductance which
one is the leader
current or voltage?
Voltage leads the current
46.
in series with gas
valve.,What does a
water flow switch
do?
Automatic safety control (normally
open). Senses water flow and switch
closes
42.
43.
44.
60.
Two causes for
induced draft
switch failure?
Failure of motor and blockage
61.
What are
Thermopiles?
Thermopiles are a collection of
thermocouples connected in series.
62.
What are the
two types of
bearings?
Sleeve or ball bearing
63.
What causes a
noisy lifting
flame?
High pressure
What
determines the
strength of the
magnetic
field?
The strength of the current
65.
What does a
flame rod do?
Senses a pulsating dc current that signals
flame is present.
66.
What does a
high pressure
control do in a
steam boiler
and at what psi
does it open?
Automatic safety control that is normally
closed. It senses high pressure in the steam
boiler and opens the switch. This is at 15 psi
when it opens.
What does a
low water cut
off do?
Automatic safety control (normally closed).
Senses water level in the boiler. If level
drops the switch opens and shuts off the
gas valve.
68.
What does an
Aquastat do?
Its an automatic operating switch (normally
open). Sense water temperature of a boiler
and closes when temperature drops.
69.
What does a
Pressure
Control Switch
(pressuretrol)
do in a steam
boiler?
Automatic control that senses high and low
steam pressure in a boiler. It closes to start
burner on low pressure and opens at high
temperature to stop the burner. Controls
steam pressure in the boiler.
What does the
start winding
do?
Has a higher resistance then run winding
causing it to be out of phase with it. This
provides more torque on start up.
71.
What is back
emf?
Counter voltage generated by the motor
72.
What is flame
ionization?
The process of heating air molecules to
allow for separation of electrons allowing
a flame to conduct an electrical current.
When an AC signal is directed through the
flame it will conduct an electrical charge
across the flame to the ground.
64.
67.
70.
73.
What is flame
rectification?
When you over size your
ground to prevent a flame
detector from getting a false
positive and thinking there is still
flame present due to carbon
build up.
74.
What is the flame failure
response test time for a
thermocouple/thermopile
residential system.
90 seconds
75.
What is the purpose of
the pilot drop out test?
To find the minimum voltage
produced by the thermocouple
that will still energize the pilot
stat. Usually between 2-4
milivolts
76.
What material is the run
capacitor and the start
capacitor made of?
Start capacitor is made of
plastic and the run capacitor is
made of metal.
77.
What milivolts indicates a
good thermopile in an
open circuit?
700-800 milivolts
78.
What part of the motor is
the stator?
Stationary part of an electric
motor.
79.
What speed does a
diaphragm open? Close?
Opens slow and closes fast
80.
What type of valve is fast
opening and fast
closing?
Solenoid valve
81.
When changing a motor
what should you do?
Check voltage supply and amp
draw while under full load.
82.
When does the starting
relay remove the start
capacitor from the
circuit?
At 85% of rated speed.
83.
When would back emf
reach maximum value?
When the motor reaches
maximum speed.
84.
Where do you use a
splash proof motor?
Outside in moist conditions
85.
Where do you use
explosion proof motors?
How are they made?
Used in explosive atmospheres
and are totally enclosed
86.
Who can change a low
water cut off?
Plumbers and steam fitters.
87.
Why must the start
winding be removed
from the circuit after
initial start up?
It will over heat and damage the
motor.
Module 14
Building as a System
© 2020 Appliance Technical Institute of Canada
UNI T 14
Unit 14 – Chapter 01: Key components
1.
The “upper ceiling, walls, windows, doors, basement walls, and basement floors” are part of which
component in the building system?
A. The building envelope
B. The building structure
C.
The building externals
D. The building environment
2.
The effects the occupants have on the building system are difficult to predict, so they can be
neglected.
A. True
B. False
3.
A clothes dryer is considered to be a part of the mechanical systems in a building.
A. True
B. False
4.
The building envelop can and should completely separate the indoors from the outdoors
A. True
B. False
5.
Vapour barriers are used to restrict the flow of moisture through the building envelope. What is used
to control the moisture levels in the building?
A. Insulation
B. Range hoods
C.
Mechanical ventilation equipment
D. Doors and windows
6.
What is the ideal relative humidity?
A. 15% to 25%
B. 25% to 35%
C.
35% to 50%
D. 45% to 65%
7.
Heat moves from cold to hot.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
1
UNI T 14
8.
Cool air can contain more water vapour than warm air?
A. True
B. False
9.
What term describes the process of air exiting a building?
A.
B.
C.
D.
Infiltration
Exfiltration
Stack effect
Distribution effect
10. What term describes the process of air entering a building?
A.
B.
C.
D.
Infiltration
Exfiltration
Stack effect
Distribution effect
11. What condition does stack effect create on the lower levels?
A. High humidity
B. Neutral pressure
C.
Positive pressure
D. Negative pressure
12. What condition does wind effect create on the leeward side of the building?
A. High humidity
B. Neutral pressure
C.
Positive pressure
D. Negative pressure
13. The combustion air supply openings required by CSA B149.1 code are designed to replace the air
exhausted by mechanical exhaust devices as well as the air used by gas appliances.
A. True
B. False
14. Pressure induced backdrafting is the reversal of the flow of flue gases out of the building caused by
negative pressure in the building?
A. True
B. False
© 2020 Appliance Technical Institute of Canada
2
UNI T 14
15. What is the maximum house depressurization limit (HDL) that a natural draft vented appliance
should be exposed to?
A. 1 Pa (.004” wc)
B.
Pa (.02” wc)
C.
10 Pa (.04” wc)
D. 1 Pa (.0 ” wc)
© 2020 Appliance Technical Institute of Canada
3
UNI T 14
Unit 14 – Chapter 02: Gas technician/fitter use of the building as a system
1.
Rooms with northern exposure are likely to have greater heat loss, air infiltration or window
condensation problems than other rooms?
A. True
B. False
2.
What component of the building envelope protects the underlying layers of the building envelope
from the driving forces of wind, rain, ground water, and sunlight?
A. Air barrier
B. Building skin
C.
Insulation
D. Vapour barrier
3.
What is the typical thickness of the plastic vapour barrier?
A. 2 mil
B. 4 mil
C.
6 mil
D. 8 mil
4.
Where is a vapour barrier installed in the building envelope?
A. Interior side of the insulation
B. Both sides of the insulation
C.
Either side of the insulation
D. Exterior side of the insulation
5.
What will happen to relative humidity during winter in a house if the vapour barrier has not been
made continuous?
A. Relative humidity in the house will increase
B. Relative humidity in the house will decrease
C.
6.
Relative humidity in the house will not be affected
Heat always travels upward.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
4
UNI T 14
7.
On an older home that has undergone some updates, where will the greatest heat loss occur?
A. Through walls
B. Through ceilings
C.
Through windows
D. Unknown until an assessment of the existing building envelope is done
8.
An insufficient supply of makeup and combustion air can cause what to occur?
A. Positive pressure in a building
B. Negative pressure in a building
C.
Increase draft and reduce efficiency
D. Decrease infiltration of contaminants from soil or walls
9.
What method should be used to determine the proper size of the space heating equipment for a
specific site?
A. Ask the customer
B. Room by room heat loss calculation
C.
Rule of thumb based on square footage
D. Rule of thumb based on the type of house
10. What type of mechanical ventilation system creates a negative or suction pressure and fresh air
enters the building by infiltration?
A. Balanced
B. Direct duct
C.
Supply only
D. Exhaust only
11. What type of mechanical ventilation system delivers fresh air under pressure and depends on
exfiltration for the removal of stale air?
A. Balanced
B. Direct duct
C.
Supply only
D. Exhaust only
12. What type of mechanical ventilation system supplies and exhausts air?
A. Balanced
B. Supply only
C.
Exhaust only
D. Through-the-wall
© 2020 Appliance Technical Institute of Canada
5
UNI T 14
13. Clothes dryers can be vented inside to capture heat energy.
A. True
B. False
14. What will be the likely effect on relative humidity of a growing number of occupants in a tightly
constructed house?
A. Relative humidity in the house will increase
B. Relative humidity in the house will decrease
C.
Relative humidity in the house will not be affected
D. None of the choices would likely occur
© 2020 Appliance Technical Institute of Canada
6
UNI T 14
Unit 14 – Chapter 03: Assessment tools for the building as a system
1.
If a heat loss calculation determines that the heat loss for a building is 100 000 Btu/h, what is the
minimum output rating for a new space heating appliance to be installed in the building?
A. 80 000 Btu/h,
B. 100 000 Btu/h,
C.
120 000 Btu/h,
D. 140 000 Btu/h,
2.
If a heat loss calculation determines that the heat loss for a building is 100 000 Btu/h, what is the
maximum output ratings for a new space heating appliance to be installed in the building?
A. 80 000 Btu/h,
B. 100 000 Btu/h,
C.
120 000 Btu/h,
D. 140 000 Btu/h,
3.
If a heat loss calculation determines that the heat loss for a building is 100 000 Btu/h, what is the
minimum input rating of a 90% efficient heating appliance that can be installed in the building?
A. 80 000 Btu/h,
B. 100 000 Btu/h,
C.
111 100 Btu/h,
D. 140 000 Btu/h
4.
In all cases, a heating system that is sized to meet the calculated heat loss of the building will operate
more efficiently than one that is oversized
A. True
B. False
5.
R value of each layer of material in the building envelope is added together to determine the total
thermal resistance of the wall.
A. True
B. False
6.
What is the outside design temperature (ODT)?
A. Is the average coldest temperature in a region
B. The coldest day in recent history in a region
C.
The average warmest winter temperature in a region
D. The hottest day on record in a region
© 2020 Appliance Technical Institute of Canada
7
UNI T 14
7.
What is R Value?
A. Heat loss
B. Ratio value
C.
Transmission loss
D. Resistance value
8.
What is the maximum allowable pressure difference is in all conditions if any non-direct vent fuel
fired, vented combustion appliances are present?
A. 1 Pa
B. 5 Pa
C.
10 Pa
D. 15 Pa
9.
Backdrafting causing spillage of flue gases can cause carbon monoxide poisoning?
A. True
B. False
10. What equipment should be employed throughout a house depressurization test?
A. Draft gauge
B. CO detector
C.
Incense stick
D. Smoke pencil
11. What is the best method of ensuring that negative building pressure never causes pressure-induced
backdrafting in a gas appliance?
A. Install a direct-vent appliance
B. Perform a depressurization test
C.
Revent the central vacuum system
D. Replace bathroom and kitchen fans with an HRV
12. A passive depressurization test uses only the exhaust equipment in the building.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
8
UNI T 14
Unit 14 – Chapter 04: Indoor air quality
1.
Wood smoke is a form of biological pollution.
A. True
B. False
2.
What is the word used to define the circulation and purification of air in an enclosed space?
A. Ventilation
B. Substitution
C.
Air Treatment
D. Humidification
3.
What is the minimum ventilation rate in a room with a master bedroom in a dwelling unit?
A. 0.14 m2
B. 0.28 m2
C.
05 L/s
D. 10 L/s
4.
If a room is mechanically cooled in summer, what is the ventilation rate required?
A. 0.5 ACH
B. 1 ACH
C.
1.5 ACH
D. 2 ACH
5.
An exhaust fan system in a dwelling causes a positive pressure due to suction force within the
dwelling.
A. True
B. False
6.
What will be the effect on relative humidity of introducing ventilation air to the building during the
heating season?
A. Increase relative humidity
B. Decreased relative humidity
C.
No effect on relative humidity
© 2020 Appliance Technical Institute of Canada
9
UNI T 14
7.
What is the problem with supply-only systems in leaky structures?
A. Higher cost to ventilate
B. Excessive depressurization
C.
Lead to a build up of pollutants
D. Can drive moist air into wall cavities
8.
What is the danger of having too little ventilation in a dwelling?
A. Higher cost to ventilate
B. Excessive depressurization
C.
Lead to a build up of pollutants
D. Can drive moist air into wall cavities
9.
Of the two methods of measuring the effectiveness of a filter, the dust spot efficiency method is a
better indicator for household dust particulate.
A. True
B. False
10. The best way to remove odours from a house is by filtration.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
10
Answers
Unit 14 – Chapter 01: Key components
1. A
2. B
3. A
4. B
5. C
6. C
7. B
8. B
9. B
10. A
11. D
12. D
13. B
14. A
15. B
Unit 14 – Chapter 02: Gas technician/fitter use of the building as a system
1. A
2. B
3. C
4. A
5. B
6. B
7. D
8. B
9. B
10. D
11. C
12. B
13. B
14. A
Unit 14 – Chapter 03: Assessment tools for the building as a system
1. B
2. D
3. C
4. A
5. A
6. A
7. D
8. B
9. A
10. B
11. A
12. A
Unit 14 – Chapter 04: Indoor air quality
1. A
2. A
3. B
4. A
5. B
6. B
7. D
8. C
9. A
10. B
© 2020 Appliance Technical Institute of Canada
2
G2 Gas Technician Module 14
1.
1993
What year did the
OBC start making
houses tighter?
12.
The buoyancy of hot air.
What principal does a
natural draft appliance
rely on?
2.
The air barrier is located between the
bricks and wood studs. It allows
moisture to be removed through
venting.
What is the function
of the air barrier
and where is it
located?
13.
By using a sealed combustion
appliance
3.
Appliance btuh input, type of building
construction, and method of venting
flue products
When sizing
combustion air
what must a gas
tech know?
A method for
minimizing negative
pressure in a
combustion
appliance?
14.
Change in state with no change in
temperature
What is latent heat?
15.
What is Flue Effect?
Change in temperature with no
change in state
What is sensible heat?
Appliance venting is often path of
least resistance. So reconsider using
natural draft appliances if a large
capacity air-exhausting appliance is
used in the structure.
16.
Conditioned air will be forced from
the building envelope, inefficient
How can positive
pressure affect the
building envelope?
As the more occupants increase the
relative humidity will also increase.
Cooking, bathing, smoking and plain
old breathing.
How do occupants
affect the building
system? What are
some actions that
do this?
17.
Curling shingles in summer and
icicle dams in the winter
Name 2 signs of poor
attic ventilation.
18.
Decrease
Balloon frame, Double/solid brick,
platform (most common)
What are three
types of building
construcion?
Introducing ventilation
air in the winter will
increase/decrease
relative humidity?
19.
Decreases
Biological(mold, mildew, bacteria),
chemicals (off -gasing of furniture,
carpets and building materials), dust
from inside and outside, any
combination of these
Pollution sources in
the building
envelope
Relative humidity
increases/decreases
when air is heated?
20.
ERV uses an aluminum core giving
greater heat transfer and moisture
control. HRV uses a plastic core
What is the difference
in an ERV and HRV
21.
Blowing into attic or wall cavity
How is insulation
added to balloon
type construction?
Foundation and floor slabs, walls,
roofs, and windows and doors
What comprises the
building envelope?
22.
From high to low
Heat and moisture will
always from from a
area of ________
concentration to a
area of _________
concentration.
23.
High relative humidy
If a house has poor
ventilation what would
the affect be on
indoor air quality?
24.
Hot air will rise to the top of the
building and escape through the
cracks. This may cause negative
pressure in the basement starving
gas fired appliances
What is stack effect in
building pressure?
25.
Humidistat
What energizes the
high speed fan in an
HRV?
4.
5.
6.
7.
8.
9.
10.
11.
The building envelope, external
environment, mechanical systems,
and occupants
The buildings differential pressure
Buildings exposed to high winds can
cause positive pressure on the
windward side and negative on the
leeward side. Can lead to occupant
discomfort and starved gas fired
appliances.
When changing a
part of the heating
system what 4
factors must the
gas technician take
into account?
What does a
passive
depressurization
test measure?
What is Wind
Effect?
26.
If in a windy area it can cause cooling
in the winter or a similar affect can be
caused by tree shade in the summer
External
Environment
affects on the
building.
27.
Impingement, straining and
electrostatic precipitation
How do filters
clean air?
28.
Improperly designed or installed
HVAC can cause air to leak from ducts
short cycling the furnace. This can
lead to poor occupant comfort and
removal of combustion air from
appliance rooms.
What is Duct
Effect?
increase
How will a poorly
insulated build
effect furnace run
time
increase/decrease?
29.
30.
It is a poor conductor of heat and will
prevent the ex filtration indoor heat to
the outside.
What does
insulation do?
31.
It is used to maintain proper humidity
levels inside the house. In winter if not
present the relative humidity will
decrease causing it to feel colder
then it is.
What is the
function of the
vapour barrier?
Low speed
What speed does
a HRV use for
continuous
ventilation?
32.
38.
Other rooms - 10 cfm
What cfm ventilation
does the ontario
building code
require in the master
bedroom and all
other rooms?
39.
Outdoor air will be sucked into the
house by path of least resistance.
Sometimes this is your appliances
exhaust vent. Can lead to spillage
and CO poisoning
How does negative
pressure affect the
building envelope?
Potential concerns?
40.
Outside air be brought in for
combustion and ventilation
What is required
when an appliances
input is greater than
400000 btuh?
41.
Potenially leads to severe indoor air
quality problems
If inadequate
combustion air is in
a tightly sealed
house what
happens?
42.
Preheats fresh outdoor incoming air
and expels stale warm indoor air.
Used to improve air quality and be
efficient at the same time.
How does an HRV
work?
43.
Protects the underlying material,
maintains building integrity and
reduces heat loss and heat gain
What does the skin
in the building
envelope do?
44.
Remove the source, Balanced hvac
throughout house, local exhausts
(bath, kitchen), substitute chemicals
for non-polluting ones, and Filtration
is best for remove dust pollutants
How would you
control pollution?
45.
Seal air leaks
What is the most
effective way to
reduce heat loss?
33.
Master Bedroom - 20 cfm
...
34.
Mechanical exhausting of building air
can cause a negative pressure
situation by means of the path of least
resistance. This can be your gas fired
appliance exhausts causing spillage.
What is
mechanical or
natural ventilation
effect?
35.
Negative pressure.
What is the most
common cause of
flue gas spillage
into the building
envelope?
46.
True
New construction
requires combustion
air be brought into
the furnace room?
T/F?
36.
Negative pressure, down draft and
blocked venting.
Name 3 things that
can cause
spillage?
47.
Ventilate
Best way to reduce
odors from inside
the building is?
37.
Opposites attract
What principal is
electrostatic
filtration based
on?
48.
The walls due to them having a
higher surface area then the rest of
the building parts.
What part of the
building has the
greatest heat loss?
49.
Water heaters, dryers, motors, fireplaces, wood stoves and air cleaners.
They may require more combustion and ventilation air for air exhausted
and used in combustion.
Mechanical impact consist of equipment and
appliances within the building. Name a few. What
should the gas tech consider?
50.
Yes
Can appliance with a draft hood use combustion air
from inside the building structure?
Module 15
Domestic Appliances
© 2020 Appliance Technical Institute of Canada
UNI T 15
Unit 15 – Chapter 01: Ranges
1.
What information found on the rating plate needed to determine the correct pipe size and check
individual burner gas flow?
A. Input rating
B. Manifold pressure
C.
Operating voltage
D. Minimum supply pressure
2.
The appliance regulator is usually pre-adjusted for use with the type of gas specified on the rating
plate and for a specific outlet pressure.
A. True
B. False
3.
How are gas ranges typically connected to the electrical power supply?
A. A three phase 4 wire cable
B. Hard wired into a junction box with armoured cable
C.
A power supply cord with a 120 VAC three-prong grounded plug
D. A power supply cord with a 240 VAC three-prong grounded plug
4.
The appliance regulator on a range is adjusted by changing the position of a simple converter fitting.
A. True
B. False
5.
How is the final connection to the gas supply manifold done to provide for movement of the gas
range in order to clean behind it?
A. A maximum 0.6 m long flexible metal gas connector
B. A maximum 1.0 m long flexible metal gas connector
C.
A maximum 2.0 m long flexible metal gas connector
D. A maximum 3.0 m long flexible metal gas connector
6.
To determine the required clearance to combustibles for a range, refer to the gas code over the
man fact rer s instr ctions or the rating plate
A. True
B. False
© 2020 Appliance Technical Institute of Canada
1
UNI T 15
7.
What is the allowable clearance to combustibles for a range certified for zero clearance (without
additional protection)?
A. 600mm above, 25 mm at the back
B. 750mm above, 25 mm at the back
C.
600mm above, 150 mm at the back
D. 750mm above, 150 mm at the back
8.
If you have three certified metal flexible connectors of different lengths, they will all have the same
gas flow capacity.
A. True
B. False
9.
When checking the manifold pressure, there must be gas flowing to properly read and adjust
pressures.
A. True
B. False
10. How does a sealed gas burner design maintain clean burner ports?
A. Burner cap collects debris
B. Flash tube burns of debris.
C.
Integrated drip pan gets removed and cleaned
D. Burner cap deflects debris away from the flame
11. How is the oven temperature recalibrated on mechanical style gas ovens that do not have adjustable
thermostats?
A. Adjust the temperature setting knob
B. Change the gas orifices
C.
Adjust the manifold pressure
D. Factory setting cannot be changed
12. How long should a gas range operate before adjusting the oven temperature calibration?
A. 1 minute
B. 5 minutes
C.
15 minutes
D. 30 minutes
© 2020 Appliance Technical Institute of Canada
2
UNI T 15
13. A properly adjusted burner flame should extend high enough so that the inner blue cone of the flame
is above the burner ring or grate, and able to touch the cooking vessel.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
3
UNI T 15
Unit 15 – Chapter 02: Clothes dryers
1.
If there are no manufacturer's rating plate clearances, what are the allowable code clearances to
combustibles from the top, back and sides of a domestic gas dryer?
A. 50 mm
B. 150 mm
C.
450 mm
D. 600 mm
2.
What is the maximum length of a metal connector used to connect a gas dryer?
A. A maximum 0.6 m long flexible metal gas connector
B. A maximum 1.0 m long flexible metal gas connector
C.
A maximum 2.0 m long flexible metal gas connector
D. A maximum 3.0 m long flexible metal gas connector
3.
What should be used to connect dryer moisture exhaust duct joints?
A. Foil duct tape
B. Electrical tape
C.
Cloth mesh duct tape
D. Three evenly spaced sheet metal screws
4.
The moisture exhaust duct can be connected to another gas appliance vent connector to create a
common vent.
A. True
B. False
5.
How far above ground level should the exhaust hood terminate?
A. 200 mm
B. 300mm
C.
500 mm
D. 1000 mm
6.
What determines the maximum length of the exhaust system?
A. Type of exhaust hood
B. Type of vent material
C.
Number of elbows
D. All of the choices
© 2020 Appliance Technical Institute of Canada
4
UNI T 15
7.
What will cause a gas dryer to keep running after its door is opened?
A. Faulty door switch
B. Faulty booster coil
C.
Faulty holding coil
D. Defective centrifugal switch
8.
What problem would a defective drum seal cause?
A. Dryer smokes
B. Clothes drying too slowly
C.
Drum operates, but noisily
D. Main burner does not light
9.
What is the minimum exhaust vent diameter for a gas dryer?
A. 3 inch
B. 4 inch
C.
5 inch
D. 6 inch
10. What problem would be caused by the dryer not being level?
A. Dryer smokes
B. Clothes drying too slowly
C.
Drum operates, but noisily
D. Main burner does not light
© 2020 Appliance Technical Institute of Canada
5
UNI T 15
Unit 15 – Chapter 03: Barbecues
1.
Most barbecues can be used on Propane or natural gas without any modifications.
A. True
B. False
2.
A shut-off valve is not necessary when using a quick disconnect device?
A. True
B. False
3.
Barbecues equipped with a piezo ignition can be match-lit?
A. True
B. False
4.
Aftermarket spider guard can be installed onto burner tubes.
A. True
B. False
5.
During the lighting of a barbecue, the lid must be closed.
A. True
B. False
6.
What is the maximum length of a barbeque connecting hose?
A. 0.6 m
B. 2 m
C.
3m
D. 4.6 m
© 2020 Appliance Technical Institute of Canada
6
UNI T 15
Unit 15 – Chapter 04: Lamps
1.
Soft mantles are more durable than hard mantles due to their flexibility.
A. True
B. False
2.
The purpose of the venturi assembly is to generate bright white light when heated by the flame.
A. True
B. False
3.
Indoor gas lamps should only be used in well ventilated rooms.
A. True
B. False
4.
Before starting any repairs, you should turn off the gas supply and allow the glass to cool.
A. True
B. False
5.
How often should a gas lamp be cleaned?
A. Weekly
B. Monthly
C.
Annually
D. Bi-annually
© 2020 Appliance Technical Institute of Canada
7
Answers
Unit 15 – Chapter 01: Ranges
1. A
2. A
3. C
4. A
5. C
6. B
7. B
8. B
9. A
10. D
11. A
12. C
13. B
Unit 15 – Chapter 02: Clothes dryers
1. B
2. C
3. A
4. B
5. B
6. D
Unit 15 – Chapter 03: Barbecues
1. B
2. B
3. A
4. A
5. B
6. C
Unit 15 – Chapter 04: Lamps
1. B
2. B
3. A
4. A
5. C
7. A
8. B
9. B
10. C
G2 Gas Technician Module 15
A dryer motor
switches from start
mode to a run
mode using what
switch?
Centrifugal switch
Glow coil system
how does it work
as an ignition
system?
The glow coil is a resistance wire
mounted on a cermaic block connected
to a step down transformer that is
mounted on the valve body. When
power is applied the coil glows
producing enough heat to ignite the
gas.
How can you tell a
hot and neutral in
a moulded flat
cord?
The exterior of the cord will have a
smooth side and a ribbed side. Smooth
is hot and ribbed is neutral.
4.
How does
conduction work?
Transfer of heat through direct contact.
Particle to particle
5.
How does
convection work?
Transfer of heat is by heat currents.
6.
How does radiant
heating work?
Heat rays emitted from a heat source.
Localized heating.
7.
How does the
Standing pilot
work on a top
burner ignitor?
What are the
variations of the #
of pilots?
A continuously lit pilot that once the
control valve calls for gas it will ignite
it. Can have one pilot for each burner,
one pilot for two burners and one pilot
for all four burners
How far should a
dryer duct
terminate from a
service regulator?
3 ft clause - 7.5.2
How hot does a
ignitor get in a
glo-sil burner?
2200 F
10.
How many valves
does a Glo-Sil
burner have?
11.
12.
1.
2.
3.
8.
9.
13.
If a three pronged cord has
black white and green
leads. What are they?
Black is hot, white is neutral
and green is ground
14.
If the dryer fires but the
drum doesn't turn, what
could be the problem?
Broken belt or seized drum
15.
If the flash tube does not
light the burner but has a
standing pilot at the base
of the tube what would
cause this?
To little air or to much gas.
16.
If you convert a gas lamp
what must you do?
Change orifice, change air
ratio, and note changes on
rating plate
17.
If you have flame flashback
beneath the control panel
on aBBQ, what is the cause?
Blocked venturi tube
18.
In a BBQ what would
placing to many lava rock
or briquettes cause?
Premature burner burn-out
19.
Is a drip/dirt pocket
required on the fuel supply
on a residential gas dryer?
No clause 6.13.1.c)
20.
Malfunctions that the warp
switch sense.
main burner doesnt light, pilot
fails to light, and a faulty pilot
flame.
21.
Name three types of
Clothes dryer burner
ignition systems.
Constant pilot, glow-coil and
glo-sil
22.
Two different types of Top
burner ignitors.
Standing pilot and Electric
ignitor
23.
Types of gas ranges
Free-standing, built-in and
dual fuel
24.
Types of heat transfer
Convection, conduction and
radiation
It has two valves that both need to be
open for the gas to flow.
25.
What are the allowable
clearances to combustibles
fora residential gas dryer?
6"
How should a
domestic clothes
dryer be
installed?
On a solid level floor and must be level
why it is operating.
26.
What are the two ways you
light a gas lamp?
If a flash tube fails
to light the burner
what can be a
cause?
To much air in the mixture.
By an electrode that is
manually operated with a
switch or automatic with a
photo sensor and manually
using an open flame.
27.
What are two causes of a
yellow flame for a gas lamp
with a mantle?
Broken mantle, not enough air
28.
29.
30.
31.
32.
33.
34.
35.
What are
two
different
types of
convection
an oven
uses.
Natural convection (warm air rises and cool air
descends) and Forced convection (heat
produced by the burner is circulated evenly
with a fan)
What color
does a
mantleequipped
gas lamp
burn?
White hot and gives off light.
What does
a warp
switch do?
Acts as a safety device to break the circuit to
the glow coil and pilot valve during a
malfunction.
What does
the flash
tube do?
Used in stand pilot systems, once control valve
is opened gas flows down tube drawing in
combustion air with it. It flows towards the pilot
and ignites. A flashback occurs back up to tube
consuming all the gas. It ignites the burner and
gas no longer is in the tube.
What
ignition
system
uses a
warp
switch?
Glow coil system.
What is are
some
prohibited
practice in
venting a
moisture
duct?
Do not connect to a vent connector, vent or
chimney and do not use sheet metal screws to
secure it. Use duct tape.
What is a
sign that
the spider
guard is
blocked on
the BBQ?
A yellow and lazy cooking flame.
What is a
typical
electrical
connection
for a gas
range?
120 V 60 HZ, two-wire with a ground.
36.
What is the max hose length
you can use on a BBQ?
30 ft
37.
What is the maximum
allowable clearance to
combustibles for a range
certified for zero clearance?
0" clause - 4.13.2
38.
What is the maximum length
of a flexible metal
connector?
6 ft
39.
What is the minimum size
and type of wire that can be
used for a 120 V, 15 A indoor
range?
14 gauge NMD
40.
What is the purpose of the
appliance regulator?
To reduce working pressure
down to manifold pressure
41.
What is the purpose of the
radiant sensor in a glow sil
burner?
To prove pilot.
42.
What is the voltage on a
glow coil system?
110 - 120 V
43.
What kind of duct is
acceptable to exhaust the
dryer?
Must be non-combustible, or
certified as a class 1 air duct
as per the CAN/ULC-S110
44.
What must a flex connector
be connected to? What else
must be there?
Must be connected to rigid
pipe with a shut off valve
immediately upstream of the
connector.
45.
What must be done if a duct
travels through an unheated
space?
It should be insulated and
sloped downward towards
the exhaust hood.
46.
What temperature does a
radiant sensor open?
2200 F
47.
What type of diagram is
used to determine sequence
of operation?
Ladder or schematic diagram
48.
What type of gas valve is
used in a glow sil burner
system?
Redundant
49.
What types of appliances
must use a flexible metal
connector?
Appliances that vibrate,
expand and contract or other
movements that could
damage a rigid connection.
50.
What types of ducts would
you use on a moisture
exhaust duct?
Rigid or flexible metal duct.
Rigid is preferred as it is less
likely to be crushed.
51.
What would cause the gas dryer to keep running after it's door is opened?
Broken door switch
52.
Where can specific information about a gas dryer be located?
In the manufactures guidelines and the rating plate
53.
Where is the shut off installed on the corrugated metal connector?
Immediately up stream
54.
Where must you vent a moisture exhaust duct?
Outdoors
55.
Where would you find the clearances for a clothes dryer?
Rating plate or B149.1
56.
Why must there be gas flow to properly read working pressure?
If there is none you are reading static pressure.
Module 16
Domestic Gas-Fired
Refrigerators
© 2020 Appliance Technical Institute of Canada
UNI T 16
Unit 16 – Chapter 01: Operation
1.
The condenser expels the heat removed from the refrigerator compartment into the ambient air.
A. True
B. False
2.
What is the purpose of thermal mastic?
A. A liquid absorber
B. A heat transfer compound
C.
A heat insulation compound
D. To sense the flame temperature
3.
What percentage of liquid ammonia evaporates into the freezer compartment side of the evaporator?
A. 10%
B. 50%
C.
90%
D. 100%
4.
What mixture drops down the return tube to the absorber tank?
A. Ammonia and air
B. Liquid ammonia and water
C.
Ammonia and water vapour
D. Ammonia and hydrogen vapour
5.
In order to increase the amount of cooling, the thermostatic gas valve will decrease the size of the
flame.
A. True
B. False
6.
Generally, the bypass screw is factory-adjusted and should not be modified.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
1
UNI T 16
7.
How is a burner orifice cleaned?
A. With a small file
B. With a min hand drill set
C.
With a stiff brass bristle brush
D. Soak it in non-oily solvents and then blow air through it.
8.
The main function of the orifice housing is to provide a correct air-gas ratio.
A. True
B. False
9.
Ammonia gas is corrosive and may be fatal if inhaled.
A. True
B. False
10. Gas Absorption heat pumps have higher operating efficiencies than electric heat pumps.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
2
UNI T 16
Unit 16 – Chapter 02: Installation procedures
1.
A refrigerator installed in an occupied area of a dwelling unit must be direct vented.
A. True
B. False
2.
Increasing the clearance at the back of the refrigerator will improve venting.
A. True
B. False
3.
An upper side vent is preferred over a top-mounted vent.
A. True
B. False
4.
To allow the condensation to flow out of the housing, the vent housing for a sealed combustion vent
must be:
A. Less than 900 to the ground
B. More than 900 to the ground
C. Less than 450 to the ground
D. More than 450 to the ground
5.
An absorption refrigerator is noiseless.
A. True
B. False
6.
Why does a gas-fired refrigerator have to be installed level?
A. So it drains properly
B. To ensure it vents properly
C. So the door will swing smoothly
D. It depends on gravity to move the liquids and gases inside
7.
How long does the refrigerator need to be operating before you can check whether it is operating
properly?
A. 10 minutes
B. 30 minutes
C. 6 to 8 hrs.
D. 24 hrs.
© 2020 Appliance Technical Institute of Canada
3
UNI T 16
8.
After the installation checks are complete, how long should the refrigerator run before the customer
places any food in it?
A. 10 minutes
B. 30 minutes
C.
6 to 8 hrs.
D. 24 hrs.
9.
Ice buildup on the fins of the evaporator does not reduce the efficiency of the refrigerator.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
4
UNI T 16
Unit 16 – Chapter 03: Maintenance and servicing
1.
After you have cleaned all of the burner components, there is still a yellow, lazy flame what should be
checked next?
A. Gas leak
B. Gas pressure
C.
Evaporator leak
D. Thermocouple
2.
For units that are supplied with a CO sensor, how often should it be tested?
A. Daily
B. Weekly
C.
Monthly
D. Annually
3.
What is wrong if you notice a yellow substance on the tubes?
A. Gas leak
B. Refrigerator not level
C.
Flame contacts the tube
D. There is a leak in the absorption system
4.
Why is it important to keep the flue clean?
A. To reduce gas consumption
B. To improve the heat transfer
C.
To avoid incomplete combustion
D. All of the choices are correct
5.
When adjusting the minimum heat input, what can happen if the setting is not low enough?
A. Flame lifting
B. Over-cooling
C.
Undercooling
D. Incomplete combustion
6.
When adjusting the minimum heat input, what can happen if the setting is to low?
A. Over-cooling
B. Undercooling
C.
Incomplete combustion
D. Flame can be blown out by drafts
© 2020 Appliance Technical Institute of Canada
5
UNI T 16
7.
What tool is used to clean the condenser?
A. Scraper
B. Paintbrush
C.
Dremel tool
D. Hand Wire brush
8.
Why is it important to keep the condenser and absorber fins clean?
A. To ensure good heat transfer
B. To reduce flame impingement
C.
To ensure complete combustion
D. To stop them from being scorched or blistered
9.
If the boiler section is hot and the absorber section is warm, what does this indicate?
A. The evaporator is blocked
B. Thermocouple tip not in position
C.
An internal leak in the evaporator
D. The hydrogen circuit has lost its charge
© 2020 Appliance Technical Institute of Canada
6
Answers
Unit 16 – Chapter 01: Operation
1. A
2. B
3. C
4. D
5. B
6. A
7. D
8. A
9. A
10. B
Unit 16 – Chapter 02: Installation procedures
1. A
2. B
3. B
4. A
5. A
6. D
7. B
8. C
9. B
Unit 16 – Chapter 03: Maintenance and servicing
1. B
2. B
3. D
4. D
5. B
6. D
© 2020 Appliance Technical Institute of Canada
7. B
8. A
9. A
1
G2 Gas Technician Module 16
1.
How does the
absorber operate
in an absorption
system?
The absorber is connected to the
evaporator by piping and it draws the
refrigerant out of the evaporator and
mixes with it to become a solution.
(principal of absorption)
9.
What does
the
generator
do in an
absorption
system?
Refrigerant and absorber must be separated
for cooling process to continue to work. In the
generator the refrigerant/absorber solution is
heated to separate the refrigerant again by a
gas fired burner. Once separated the
refrigerant travels to the condenser and the
absorbent travels back down to the absorber
chamber attracting more refrigerant.
2.
How does the
evaporator
operate in an
absorption
system?
This is the location where the refrigerant
evaporates from a liquid to a vapour.
During this process the refrigerant
absorbs heat from the surrounding area
and cools it.
10.
What
happens if
there is a
hydrogen
leak in the
refrigerator?
If there is a leak the cooling unit will feel
slightly warm at the generator and extremely
warm at the absorber
3.
How does the
principal of
absorption work?
It relies on two chemicals having an
affinity or attraction to each other. Once
they are separated they will try to get
back together.
4.
How do you
control the
capacity of an
absorption
system?
You do this by controlling the heat
source. (gas burner) in the generator.
11.
What must a
refrigerator
on a
recreational
vehicle be?
Direct Vent
5.
Main elements of
an absorption
system
Evaporator, absorber, generator and
condenser
12.
They are based on the principal of absorption
What are some
of the safety
issues related to
using ammonia as
a refrigerant?
Classified as toxic avoid inhalation, avoid
contact with skin and eyes, and their
refrigerant coils are not field repairable.
What
principal are
gas fired
refrigerators
and air
conditioners
based on?
6.
13.
Ammonium hydroxide
7.
What does a
Three way
refrigerator
require for
operation?
120 volts AC, 12 volts DC and propane
heat source
What type
of
absorbent is
used in a
gas fired
domestic
refrigerator?
8.
What does the
condenser do?
The condenser condenses the refrigerant
back to its liquid state. This process gives
off heat, from here the liquid refrigerant
travels to back to the evaporator and the
process begins again.
14.
What type
of
refrigerant
is used in a
gas fired
domestic
refrigerator?
Ammonia
15.
What will
you notice if
there is an
ammonia
leak in the
system?
Yellow substance on the tubes. The ammonia
vaporizes leaving a yellow residue.
16.
Why must a
Domestic
gas fired
refrigerator
be leveled?
It depends on gravity for operation. If it is off
level this will cause liquids and gases to
collect in unwanted areas.
Module 17
Conversion Burners
© 2020 Appliance Technical Institute of Canada
UNI T 17
Unit 17 – Chapter 01: Guidelines for converting appliances
1.
A conversion to natural gas will improve an improperly sized system?
A. True
B. False
2.
What combustion chamber design is most suitable for conversion?
A. Pulse type
B. Updraft type
C.
Revertible type
D. Semi-revertible
3.
A gas fired will have lower flue gas temperatures than the temperature of emissions from oil or solidfuel appliances.
A. True
B. False
4.
What could be the result of an oversized unlined chimney?
A. Sooting
B. Overheating
C.
Flue gas condensing
D. Too much draft action
5.
What must be done if there are no manufacturer’s instructions for conversion of the appliance?
A. Hire an engineer
B. Do not attempt the conversion
C.
Find a similar appliance with instructions
D. Seek approval of the authority having jurisdiction
6.
What is the maximum setting of a high-limit control on a forced-air furnace?
A. 1200 C (2500 F)
B. 1000 C (2120 F)
C.
2500 C (1200 F)
D. 2000 C (392 F)
© 2020 Appliance Technical Institute of Canada
1
UNI T 17
Unit 17 – Chapter 02: Preparation for conversion
1.
What is the purpose of a smoke test?
A. Check chimney for leaks
B. Check venting system for leaks
C.
Check furnace combustion chamber for leaks
D. Check for proper operation of the venting system
2.
What is the purpose of a water test for conversion purposes?
A. Check chimney for condensing
B. Check boiler heat exchanger for leaks
C.
Check furnace heat exchanger for leaks
D. Check the boiler make-up water supply quality
3.
The flue outlet has to be plugged before a smoke test is performed.
A. True
B. False
4.
If cracks are discovered in the heat exchanger of a furnace, what must be done?
A. They can be repaired by welding
B. They can be repaired with furnace cement
C.
The heat exchanger of appliance must be replaced
D. They can be repaired with high temperature silicone
5.
After the appliance has been checked and repaired, what is done next?
A. Mount the burner
B. Select the proper orifice size
C.
Select the proper burner air tube
D. Check the combustion air and venting system
6.
Most masonry chimneys use for oil burners will be too large and should have a liner installed for the
gas conversion.
A. True
B. False
7.
An adjustable barometric draft control device can be located in a separate room as the appliance.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
2
UNI T 17
8.
What is the purpose of the fan or blower on a natural draft power conversion burner?
A. Provide pressurized combustion air
B. Overcome the resistance of the appliance
C.
Force the flue gas through the venting system
D. Draw gas in from the zero governor regulator
9.
A conversion burner should be selected that has a 30% greater input than the previous oil burner to
avoid flue gas condensation.
A. True
B. False
10. How many Btu are contained in one US gallon of No. 2 fuel oil?
A.
Btu’s
B.
Btu’s
C.
D.
,
,
Btu’s
Btu’s
11. Revertible appliances are not recommended for conversion?
A. True
B. False
12. Are inshot burners accepted for use on a Type B combustion chamber? If so, under what conditions?
A. No
B. Yes always
C.
Yes, if a revertible flue travel.
D. Yes, as long as the combustion chamber liner and insulation are installed.
13. How should the burner air tube and mounting plate be sized?
A. It shall be . ” long
B. End of the tube is flush with the inside of the combustion chamber.
C.
End of the tube extends into the inside of the combustion chamber by at least
.”
D. End of the tube is flush with the outside of the combustion chamber.
© 2020 Appliance Technical Institute of Canada
3
UNI T 17
Unit 17 – Chapter 03: Burner installation and flue gas analysis
1.
What is the breeching pipe?
A. A flue gas exhaust pipe that penetrates the roof
B. A flue gas exhaust pipe that penetrates the chimney
C.
A flue gas exhaust pipe that connects directly to the appliances
D. A flue gas exhaust pipe that connects downstream of the draft regulator
2.
What is the term used to describe the difference in temperature between the flue gas in the vent and
the ambient air?
A. Net stack temperature
B. Gross stack temperature
C.
Ultimate stack temperature
D. Theoretical stack temperature
3.
What is the primary cause of incomplete combustion when the appliance is firing at the correct
input?
A. lack of air
B. lack of gas
C.
too much air
D. too much gas
4.
Perfect combustion can be maintained in a combustion chamber?
A. True
B. False
5.
What are the products of complete combustion?
A. heat, carbon monoxide and water vapour
B. heat, carbon dioxide and carbon monoxide
C.
heat, carbon dioxide, water vapour and nitrogen
D. heat, carbon dioxide, carbon monoxide and nitrogen
6.
How many cubic feet of combustion air is required for perfect combustion of one cubic foot of
propane gas?
A. 10 cubic feet (0.28 m3)
B. 16 cubic feet (0.45 m3)
C.
25 cubic feet (0.71 m3)
D. 32 cubic feet (0.91 m3)
© 2020 Appliance Technical Institute of Canada
4
UNI T 17
7.
Which element of the flue gas analysis is the best indication of how much excess air is being
introduced into the combustion chamber?
A. O2
B. N2
C.
CO
D. CO2
8.
For a flue gas analysis of natural gas, a 7% reading for both CO 2 and O2 would indicate approximately
how much excess air?
A. 10%
B. 25%
C.
50%
D. No excess air
9.
What would be the temperature of the flue gas if an appliance was 100% efficient?
A. 130°F (54°C)
B. 325°F (205°C)
C.
3550°F (1950°C)
D. Room temperature
10. At what level must the level of carbon monoxide remain below (on an air-free basis)?
A. 0 PPM
B. 20 PPM
C.
50 PPM
D. 100 PPM
11. Without sufficient air for combustion in a gas-fired appliance, which would you expect to find in the
products of combustion?
A. Ethane
B. Oxygen
C.
Hydrogen Sulfide
D. Carbon monoxide
12. Approximately what pressure should the barometric damper be adjusted to, in order to achieve a
neutral pressure point at the burner?
A. -. WC”
B.
C.
WC” to -.
WC”
-.
WC” to -.
WC”
D. -.
WC” to -.
WC”
© 2020 Appliance Technical Institute of Canada
5
UNI T 17
13. During the combustion of natural gas, the combustion products in the vent are cooled down below
120 F. Which of the following conditions will occur?
A. The flue products will condense and corrode the vent
B. The quantity of CO will increase
C.
The quantity of carbon dioxide will increase
D. The carbon in the flue gas will condense and plug the vent with soot
© 2020 Appliance Technical Institute of Canada
6
Answers
Unit 17 – Chapter 01: Guidelines for converting appliances
1. B
2. B
3. A
4. C
5. D
6. A
Unit 17 – Chapter 02: Preparation for conversion
1. C
2. B
3. A
4. C
5. D
6. A
7. B
8. A
9. B
10. C
11. A
12. D
13. B
Unit 17 – Chapter 03: Burner installation and flue gas analysis
1. C
2. A
3. A
4. B
5. C
6. C
7. A
© 2020 Appliance Technical Institute of Canada
8. C
9. D
10. C
11. D
12. C
13. A
1
G2 Gas Technician Module 17
1.
Before starting a
burner what should be
done?
Check firing rate on plate and check
venting
2.
Can you convert a
forced air furnace
with a secondary
heating surface on
the suction side of the
air blower?
No. Unless the heating surface
consists of a single cylinder flue
pope passing directly from the
primary heat exchange to the flue
collar and has a continuously gas
tight welded joint.
3.
Following an oil to
gas conversion where
oil tank is in the
basement what must a
gas technician do?
Remove fill pipe, cap or plug
exposed fill pipe opening and leave
vent intact. Clause 4.3.5
4.
How do you calculate
nozzle size in an oil
burner?
Gallons per hour time 1 US galon of
oil (140 000 btu)
ie: 0.75 h x 140 000 btu = 105 000
btu/h
5.
How do you check a
heat exchanger?
1. Smoke in fire chamber (plug the
flue outlet)
2. Light and mirror, check for cracks
3. warping and distortion of heat
exchanger
4. Rust Spots
5. Gaskets on joints.
6.
How do you check
combustion
efficiency?
Flue gas analysis is necessary to
properly adjust
7.
How do you
determine the firing
rate of a replacement
burner?
1. Heat loss calculations of the
building
2. Input or output on rating plate
3. Nozzle size in the burner
How is the high limit
tested on a forced
warm air furnace?
Disconnect blower or block return
air
9.
How many btu's are in
one us gallon of oil
140000
10.
How many btus is 1
Boiler Horsepower?
33 475 btuh
In the B149 code
where do you find
approved materials
for joining single wall
vent connectors?
Under vent connectors clause 8.18.3
8.
11.
12.
Is a barometric
draft control
deviced used
for oil burners
suitable for
gas
conversion?
It is not.
13.
Neutral
pressure point
has _______
pressure
below and
________
pressure
above.
Negative below and positive above.
14.
Oil fired
furnaces are
recommended
not to be
converted at a
certain age
what is age is
this?
10 years clause 4.3.5
15.
What are the
factors
governing a
conversion?
Availability of gas, efficiency if converted,
access to combustible air, satisfactory
ductwork, can a chimney liner be installed,
clearances from combustibles, manufactures
recommendations, if a water heater is also
being installed (common vent or power
vent), and age of the appliance
16.
What are the
products of
complete
combustion?
1. Carbon Dioxide
2. Water Vapour
3. Light
4. Heat
17.
What are the
responsibilities
of the installer
when
converting?
Determine that it can accept gas and will
operate satisfactory for a reasonable length
of time.
18.
What are the
three types of
combustion
chamber
designs?
1. Updraft
2. Semi-revertible
3. Revertible - conversion prohibited
19.
What are
three
undesirable
products of
incomplete
combustion?
Soot, aldehydes and Co.
20.
What causes low
resistance on the
furnace flue passage?
How can this be
corrected?
A higher then desired neutral
pressure level. Add resistance by
installing a neutral point adjuster.
31.
What must be done to
a neutral pressure
point adjuster once
the burner input has
been established?
It must be permanently locked in
place to avoid accidental
adjustments.
21.
What happens if a
blower belt is to tight?
Stresses the motor out
32.
22.
What high limit setting
should not be exceeded
on a forced warm air
converted furnace?
250 F clause 7.8.6
What must be done
when converting a
boiler?
23.
What is excess air?
Air added to ensure complete
combustion
1. Check for revirtible flue; center
line must be at leas 12" above
burner port
2. Visually inspect for leaks
3. Open drain at bottom and flush
until water is clear
4. Sediment can hide a leak at the
bottom
What is Net stack
temperature?
The difference between gross
stack temperature and the ambient
or surrounding temperature.
33.
24.
What needs to be
ensured on a neutral
pressure level?
That it is installed at the correct
height.
What is the difference
between single acting
and double acting
barometric draft control
devices?
1. Single acting can only swing
one way, it will only allow air in
from the structure.
2. Double acting swings both
ways and will allow spillage of
flue gases into the structure if
venting is blocked or has enough
downward pressure
34.
25.
What two types of
atmospheric burners
are usually used in
conversions? Where
would each be used?
Inshot - usually used on oil fired
appliances, must remove oil
combustion chamber
Upshot - usually used with coal
fired appliances, must remove
grate and ash pit doors.
35.
What types of burners
are used in a
conversion burner?
Atmospheric, fan assisted, and
power burner
36.
What types of burners
can be used in a
revertible flue?
Atmospheric is not allowed, Fan
assisted can be used but must have
spark ignition, pre-purge of
combustion air and automatic
valve with dual safety functions.
37.
When flue gas
analyzer is giving a
reading where
accuracy is in doubt
what must be done?
Compare to a known sample
38.
When would you use a
single acting
barometric draft
control device?
On an incinerator. Clause - 8.25
39.
Where do you
measure the flue gas
temperature?
Immediately upstream of the draft
hood or barometric draft regulator.
40.
Where is the neutral
pressure point
located?
Located upstream of the draft
control device.
41.
Where must a pressure
relief drop tube be
located on a boiler?
The pressure relief tube must be
withing 12" of the floor
26.
What is the minimum
clearance from
combustibles on a
single wall vent
connecter on a
converted furnace?
9" Table 8.6
27.
What is the minimum
clearance in front of a
boiler?
48"
28.
What is the minimum
gauge of steel required
for flue outlet to the
draft hood?
24 gauge clause 7.8.5
What is the ultimate
Carbon dioxide output
in perfect combustion?
NG - 11.9% LPG - 13.9%
What must be done if a
warm air furnace does
not have a revertible
flue?
Center line of the flue collar is 12"
above burner port and barometric
draft regulator can be installed so
relief opening is 12" above the
highest flue passage.
29.
30.
Module 18
Water Heaters and
Combination Systems
© 2020 Appliance Technical Institute of Canada
UNI T 18
Unit 18 – Chapter 01: Water heaters
1.
Which Code (other than the CSA B149.1) should be referenced to determine requirements for the
installation of water heaters?
A. CSA B139
B. CSA B52
C.
National Plumbing Code
D. Uniform Plumbing Code
2.
What type of water heater is permitted to be installed in a bedroom?
A. Tankless
B. Direct-fired
C.
Power-vent
D. Direct-vent
3.
What is the maximum distance of an indirect connection air break permitted for a relief valve s
discharge pipe?
A. 300 mm
B. 600 mm
C.
150 mm
D. 25 mm
4.
Referring to CSA B149.1, do the requirements of Clauses 8.2 to 8.5 apply to a direct-vent appliance?
A. Yes
B. No
5.
When a tank may be subject to back siphonage, what must be installed?
A. Vacuum relief valve
B. Vacuum breaker
C.
Check valve
D. Draft hood
6.
What is the minimum allowable clearance to combustible material for an underfired storage-type
water heater?
A. 150 mm
B. 100 mm
C.
50 mm
D. 25 mm
© 2020 Appliance Technical Institute of Canada
1
UNI T 18
7.
What type of water heater is most commonly used for residential and low-demand commercial
installations?
A. Indirect-fired system
B. Direct-fired storage heaters
C.
Tankless water heaters
D. Fin-tube water heaters
8.
What heats the stored water heated in an indirect water heating system?
A. The gas flame s hot products of combustion
B. A secondary heat transfer fluid
C.
An element immersed in the tank
D. Gas flames in contact with the tank
9.
What heats the stored water in a direct-fired storage heater?
A. The gas flame s hot products of combustion
B. A secondary heat transfer fluid
C.
An element immersed in the tank
D. Gas flames in contact with the tank
10. What is not a benefit of a tankless water heater?
A. Heats water on demand
B. Less space required
C.
Lower firing rates
D. More efficient
11. All types of fin-tube type boilers are suitable for heating potable water.
A. True
B. False
12. What makes a direct-vent water heater different from other types of water heaters?
A. Combustion products are vented directly from the unit to outdoors
B. Combustion air is vented directly to the unit from outdoors
C.
Drainage near the unit is required
D. No storage of water is available
© 2020 Appliance Technical Institute of Canada
2
UNI T 18
13. What is used to remove the products of combustion from a power-vent water heater?
A. Motor-driven fan
B. Natural draft
C.
Atmospheric pressure
D. circulator
14. What type of pilot would be used with a power-vented water heater?
A. Intermittent pilot
B. Standing pilot
C.
Constant pilot
D. Expanding pilot
15. Plastic venting material used to vent water heaters and other gas-fired appliances must meet what
standard?
A. CSA B181
B. ULC S636
C.
ULC S635
D. CSA B182
16. Condensing water heaters achieve high efficiencies by capturing
heat.
A. Latent
B. Sensible
C.
Specific
D. Practical
17. Combination systems are designed to provide a combination of domestic water heating and space
heating.
A. True
B. False
18. What is the minimum temperature that water should be stored to eliminate the growth of legionella
bacteria?
A. 140°F (60°C)
B. 120°F (49°C)
C.
180°F (82°C)
D. 100°F (38°C)
© 2020 Appliance Technical Institute of Canada
3
UNI T 18
19. How long could it take to suffer a third-degree burn if a person was exposed to water at 140°F
(60°C)?
A. 5 minutes
B. 2 minutes
C.
30 seconds
D. 4 seconds
20. In reference to a thermostatic gas control, what is the typical differential temperature maintained by
the rod and tube aquastat?
A. 20°F to 25°F
B. 10°F to 15°F
C.
5°F to 10°F
D. 15°F to 20°F
21. In reference to a thermostatic gas control, what does ECO stand for?
A. Energy Contact Open
B. Energy Cut Off
C.
Efficiency Contact Order
D. End Cycle Over
22. Residential storage-type gas water heaters have been made more resistant to accidents caused by
mishandling or improper storage of gasoline or other flammable materials. What is the common
name for this type of technology?
A. ULC
B. ECO
C.
FVIR
D. T & P
23. Pumps used to circulate domestic (potable) water must be made from stainless steel or bronze.
A. True
B. False
24. When connecting to a water heater, what minimum length of metallic piping should be installed
before connecting to plastic water distribution piping?
A.
B.
mm
mm
C.
mm
D.
mm
© 2020 Appliance Technical Institute of Canada
4
UNI T 18
Unit 18 – Chapter 02: Combination systems
1.
This term means water that is safe to drink .
A. Sanitary
B. Drinkable
C.
Potable
D. Portable
2.
Any domestic water heater can be used for space heating applications.
A. True
B. False
3.
Certified combination storage-type or a certified tankless potable water heater is intended for space
heating applications of not more than:
A. 75,000 Btu/h (22 kW)
B. 25,000 Btu/h (7.3 kW)
C.
50,000 Btu/h (14.6 kW)
D. 100,000 Btu/h (29.3 kW)
4.
All water contained in a combination system s heating piping and components must be circulated at
least once every
hrs.
A. 48
B. 24
C.
12
D. 2
5.
What is the maximum permitted water velocity if the temperature of the heating system exceeds
140°F (60°C)?
A. 3 feet per second (1 m/s)
B. 4 feet per second (1.2 m/s)
C.
5 feet per second (1.5 m/s)
D. 6 feet per second (2 m/s)
6.
The total length of supply and return piping from the water heating appliance to the terminal heating
unit must not exceed what distance?
A. 150 feet (45 m)
B. 100 feet (30 m)
C.
50 feet (15 m)
D. 25 feet (7.5 m)
© 2020 Appliance Technical Institute of Canada
5
UNI T 18
7.
Calculate the velocity of water in
USGPM .
ID tubing if the flow rate required for the heating circuit is 5.5
A. 2 ft/sec
B. 4 ft/sec
C.
3 ft/sec
D. 5 ft/sec
8.
What type of chemicals may be added to a combination system?
A. Glycol
B. None
C.
Phosphates
D. Bromide
9.
An open system has no contact with the atmosphere at any point.
A. True
B. False
10. What is installed to prevent reverse flow in a circuit?
A. Mixing valve
B. Relief valve
C.
Check valve
D. Expansion tank
11. What is installed to accommodate the increased volume of fluid within a heating system?
A. Mixing valve
B. Relief valve
C.
Check valve
D. Expansion tank
© 2020 Appliance Technical Institute of Canada
6
UNI T 18
Unit 18 – Chapter 03: Systems sizing
1.
What is the minimum size of water heater recommended for a combination system?
A. 60 USG
B. 40 USG
C.
48 USG
D. 90 USG
2.
The heating output of an air handler should exceed the calculated space heating loss of the building it
serves.
A. True
B. False
3.
What is the recommended water heater capacity for an air handler rated for 1200 cfm?
A. 60 USG
B. 40 USG
C.
48 USG
D. 90 USG
Refer to Table 5 HUD-FHA Water Heater Capacities for One- and Two- Family Living Units in Figure 3-1 (Design
worksheet).
4.
What size water heater is recommended for a house with 3 bathrooms and 4 bedrooms? (Consider
the domestic demand only.)
A. 50 USG
B. 20 USG
C.
30 USG
D. 40 USG
5.
What is the most important step to consider when determining the correct size of a water heater for
space heating applications?
A. Quote the job
B. Accurate heat loss calculation
C.
Determine the location of the thermostat
D. Select the fan coil
6.
Two factors used to determine the selection of a properly sized pump for a hydronic system are
pressure loss and
.
A. System type
B. Pipe size
C.
Flow rate
D. Tank capacity
© 2020 Appliance Technical Institute of Canada
7
UNI T 18
7.
How many USGPM are required to deliver 40,000 Btu/h?
A. 2
B. 4
C.
3
D. 5
© 2020 Appliance Technical Institute of Canada
8
UNI T 18
Unit 18 – Chapter 04: Servicing systems
1.
What is the expected reading when performing a thermocouple s open circuit test?
A. 5 mV
B. 10 mV
C.
30 mV
D. 750 mV
2.
A thermocouple must de-energize the pilotstat coil within how many seconds?
A. 5
B. 30
C.
60
D. 90
3.
A water heater equipped with an ECO will activate when the temperature of the water in the tank
exceeds
°F
A. 200
B. 250
C.
100
D. 140
4.
Water heaters equipped with rod-and-tube type thermostatic gas controls will have the TCO and ECO
wired in
with the safety shut-off valve.
A. Series
B. Parallel
C.
Bypass
D. Reverse
5.
A closed limit switch should have
resistance.
A. High
B. Infinite
C.
Variable
D. No
6.
What should be measured to determine the integrity of a flammable vapour sensor?
A. Pressure
B. Magnitude
C.
Resistance
D. Amperage
© 2020 Appliance Technical Institute of Canada
9
UNI T 18
7.
If the temperature of a NTC thermistor decreases, its resistance will
.
A. Decrease
B. Increase
C.
Not change
D. Reduce
8.
What do tankless water heaters use to ensure that there is an adequate (minimum) flow of water
through the heat exchanger?
A. Low-water switch
B. Flow sensor
C.
Check valve
D. Ohmmeter
9.
What should be used to measure a water heater s manifold pressure
A. Manometer
B. Multimeter
C.
Flushometer
D. Frometer
10. What contributes to the formation of lime scale in a water heater?
A. Sodium
B. Chlorine
C.
Hardness
D. Low pH
11. What is used to remove lime scale?
A. Pickle juice
B. Muriatic acid
C.
Sodium chloride
D. Zinc salts
© 2020 Appliance Technical Institute of Canada
10
Answers
Unit 18 – Chapter 01: Water heaters
1. C
2. D
3. A
4. B
5. A
6. C
7. B
8. B
9. A
10. C
11. B
12. B
13. A
14. A
15. B
16. A
17. A
18. A
19. D
20. D
21. B
22. C
23. A
24. D
Unit 18 – Chapter 02: Combination systems
1. C
2. B
3. A
4. B
5. A
6. C
7. B
8. B
9. B
10. C
11. D
Unit 18 – Chapter 03: Systems sizing
1. C
2. A
3. A
4. A
5. B
6. C
7. B
Unit 18 – Chapter 04: Servicing systems
1. C
2. D
3. A
4. A
5. D
6. C
7. B
8. B
9. A
10. C
11. B
G2 Gas Technician Module 18
1.
...
No a draft hood may not be altered - Clause 8.23.3
-/May a draft hood be altered? What code clause covers
this situation?
22.
...
Yes -/Is Carbon Monoxide tasteless and odourless ?
23.
...
Mineral build up -/How is lime formed inside a water
heater?
2.
...
No -/Is it acceptable to install a relief valve discharge
piping in areas that may freeze?
24.
...
Condensation -/Water in the combustion chamber is
usually a sign of what?
3.
...
No (ferrous metals contain iron) -/Ferrous metals are
acceptable for potable water applications?
25.
...
Lack of make up Air -/A cause of negative pressure in a
building is ?
4.
...
To prevent flammable vapor entering the burner -/Explain
the purpose of a Flammable Vapour Sensor?
26.
...
Recalibrate it -/If the thermostat on the control unit is
more than 20F off setpoint, what should you do?
5.
...
1'' rise per 4 Ft -/At what slope should horizontal venting
be run?
27.
...
Orifice Size -/If manifold pressure is correct and clocked
input is incorrect, what could be the problem?
6.
...
Plastic drip inside the water inlet could melt -/Why
should you not solder a fitting directly onto the cold
water inlet of a water heater?
28.
...
Manometer -/What is the most accurate way of testing
gas Manifold pressure?
7.
...
6 Inch -/What is the allowable clearance to combustibles
for single wall vent installed on gas fire water heater?
29.
...
2-5 Milli-volts -/A properly functioning pilot-stat coil
should close the pilot-stat valve when the reading on the
milli volt meter reads?
8.
...
Circulation System -/What type of system stores large
amounts of hot water for intermittent use?
30.
...
Hydronic radiant heating -/What is a dedicate water
heater system used for?
9.
...
No -/Hot water piping runs should be as long as
possible?
31.
...
Detect faulty Thermocouple -/What is the purpose of an
open circuit test?
10.
...
50ft -/What is the allowable maximum total length of
supply and return piping?
32.
...
11.
...
Circulating Pump -/What controls fluid flow between
heating units in a combination system?
Pump should be 1gpm per 10,000 Btu/h and friction loss
of 1 foot for each 40 foot run of pipe -/Rule of thumb for
pipe sizing?
33.
...
12.
...
Spiral Baffle -/What device is installed in the flue of a
residential water heater to improve heat transfer to the
water?
True -/A storage-type heater may be used in a fan-coil
combination system?
34.
...
True -/The heating output of an air handler should exceed
the calculated space heating loss of a building?
35.
...
40 gallon high-recovery or high efficiency -/What is the
minimum size and type of water heater recommended for
a combination system?
36.
...
To match the flow requirements of the heating unit
supplied by the system -/How should three-way valves
be sized?
37.
...
No -/May chemicals be used in a combination system?
38.
...
2 Inches -/What is the minimum allowable clearance to
combustibles for an underfired storage-type water
heater?
39.
...
150 Psig -/What is the maximum pressure a boiler can
produce?
40.
...
Gas Technician -/When installing gas-fired water heaters,
who is responsible for following code requirements?
41.
...
Heat from the gas flame is in direct contact with the Tank
or Pipe -/Define what Direct Fired means?
42.
...
Direct Fired Storage Heater -/The most common type of
water heater used in residential and low demand
commercial applications is?
13.
...
Change in water temperature -/What causes a rod and
tube aquastat to operate?
14.
...
Before the burner comes on -/On a power-vented water
heater, when does the exhaust fan start?
15.
...
The Flue Tube -/What acts as the heat exchanger in a
direct-fired water heater?
16.
...
By the Heat Exchanger and coils heated in the tank -/How
is stored water Heated indirectly?
17.
...
Direct Fired Water Heaters -/What type of water heater is
most commonly used for residential and low demand
commercial installations?
18.
...
Once every 24 Hours -/What is the minimum frequency of
a combination system pump cycle?
19.
...
Potable Water -/What must be used to test a combination
system?
20.
...
Yes it must be in the same room - clause 8.23.6 -/May
combustion air openings be in the same room as the draft
hood? What code clause covers this situation?
21.
...
True -/Loose wiring causes increased resistance?
43.
...
Only if they are of the direct vent type
- clause 7.27.1 -/May all types of
water heaters be installed in a
bathroom? What Clause covers this
type of installation?
44.
Can you use
chemicals in a
combination
system?
No
How can you tell a
water heater has a
build up of lime?
Sounds like it is percolating.
How does a dip tube
function?
Allows cold water to enter near the
bottom of the tank as hot water exits
the top
How do you delime
a water heater?
How do you prevent
it from starting?
Delime with a vinegar or a chemical
solution(environmentally friendly) and
prevent it with a water softener
How do you size a
circulating pump?
1 gpm for each 10000 btuh and
friction loss is 1 foot for each 40 feet
of pipe
49.
How do you size the
pumps in a
combination
system?
To match the flow requirements of the
heating system
50.
How is legionnaires
disease created?
Temperatures lower then 105 F in
ponding water.
51.
How is temp rise
determined on an
under fired storage
heater?
Inlet compared to outlet
52.
Temperature
settings on a water
heater?
Hot - 160 F
Normal - 130 F
Warm - 120 F
53.
What acts as a heat
exchanger in an
underfired storage
water heater?
The flue(baffle)
54.
What are the
components of a
direct fired storage
heater(under fired
storage heater)
Dip tube, anode, temperature and
pressure relief valve, and mixing
valve
What are the
components of a hiefficiency water
heater?
E.C.O., temperature and pressure relief
valve, anode and dip tube
45.
46.
47.
48.
55.
56.
What are the components of
an instantaneous water
heater?
Pump, pump control, flow
switch, temperature and
pressure relief valve, and a
limit control
57.
What are the normal
operating temps of a unitrol
130 F
58.
What are two reason check
valves are used in a
combination system?
To stop return water from
cooling the supply water
and to prevent cold water
from entering the rad
59.
What clearance must a direct
vent water heater have on the
burner side?
3 feet
60.
What controls the water temp
and gas pressure on a direct
fired storage heater?
Unitrol
61.
What do anodes do in a water
heater? When do you need to
change them?
Prevents the interior of the
tank from corroding and
should be changed when
its diameter is 3/8"
62.
What does an E.C.O. do?
Shuts off gas valve in a
high temperature situation
63.
What does an expansion tank
do?
To allow room for heated
water to expand so it
doesn't burst pipes
64.
What does a unitrol have in it?
Temperature and pressure
relief valve, E.C.O., Main
Gas valves, Pilot Gas Valve
and a gas regulator
65.
What improves heat transfer
in a residential water heater?
Having the baffle spiral
66.
What is a temperature control
made of in a water heater?
Which one is the sensing
element?
Rod and tube. Rod is steel
and tube is copper.
Copper is the sensing
element.
67.
What is the maximum
allowable length of supply
and return piping in a
combination water heating
system?
Max supply and return
piping is 50 feet
68.
What is the minimum size and
type of water heater that is
recommended for a
combination system?
40 gallon high-recovery or
high efficiency gas-fired
water heater
69.
What is the purpose of a
circulating pump?
To keep fluid circulating the
pumping system
70.
What is the purpose of a
mixing valve and what is the
temperature setting?
Controls water temperature
and sets it at 120 F
71.
What is the purpose of a pressure reducing valve?
To reduce pressure from street to system pressure
(12 psi)
72.
What metals are not acceptable in potable water applications?
Ferrous metals
73.
What must be done with a Twinned Water heater system to ensure it runs
properly?
Inlet and outlet piping must have equal resistance
on each tank.
74.
What temp does a temperature and pressure relief valve fusible link melt at?
Pressure relieve at?
Melts at 210 F and relieves itself at 150 psi
75.
What temperature difference do you want from inlet to outlet on a
combination system?
20 F
76.
What type of solder do you use when soldering water lines?
Lead free
77.
Where are isolation valves installed on a combination system?
At each unit and wherever necessary
Module 19
Forced Warm-Air
Heating Systems
© 2020 Appliance Technical Institute of Canada
UNI T 19
Unit 19 – Chapter 01: Forced-air furnaces
1.
If the venting on a high efficiency furnace runs through unheated spaces, what must be done?
A. It must be insulated
B. It must be protected from damage
C.
It must be increased by one pipe size
D. Vents from condensing appliances can NOT go through unheated spaces
2.
How would an installer determine the existing ductwork is adequately sized for the new highefficient furnace?
A. Complete a heat loss calculation
B. Check the blower motor amp draw
C.
Perform an external static pressure test
D. C
3.
fi
If a HRV i
he e
e a
ed i c
j
e i ei
ci
i hi
i haf
he
a
ace
fac
e
ecifica i
he e i he HRV
a
ai
c
ec ed
he
furnace system?
A. On the return air ducting but at least 3 m from the furnace
B. On the supply air ducting but at least 3 m from the furnace
C.
On the return air ducting but no more than 3 m from the furnace
D. On the supply air ducting but no more than 3 m from the furnace
4.
If a furnace system has air-conditioning added, where does the cased coil go?
A. Downstream of the burner and downstream of the blower
B. Upstream of the burner and upstream of the blower
C.
Downstream of the burner but upstream of the blower
D. Upstream of the burner but downstream of the blower
5.
In what position(s) can condensing furnaces be installed?
A. Up or horizontal left only
B. Up or horizontal left or horizontal right
C.
Up, down, horizontal right and horizontal left
D. Only positions approved by the manufacturer
6.
What is the AFUE rating of a high-efficiency (condensing) furnace?
A. 83% or greater
B. Greater than 83%
C.
90% or greater
D. Greater than 90%
© 2020 Appliance Technical Institute of Canada
1
UNI T 19
7.
Which category of furnace is a high-efficiency appliance?
A. Category I
B. Category II
C.
Category III
D. Category IV
8.
What type(s) of furnace(s) use an inducer fan?
A. Mid-efficiency only
B. High-efficiency only
C.
Mid-efficiency and high-efficiency
D. Low-efficiency, mid-efficiency, and high-efficiency
9.
Why is condensate considered corrosive?
A. It has a low pH and low acidity
B. It has a high pH and low acidity
C.
It has a high pH and high acidity
D. It has a low pH and high acidity
10. What is the draft pressure in the vent from a condensing furnace?
A. Neutral
B. Positive
C.
Negative
D. Positive or negative depending on input
11. How are Type BH vents sized?
A. U i g he f
B. U i g he e
C.
ace
i e
a
fac
a
fac
e
ie a
e
e
ie a
e
Using the vent sizing tables in the CSA B149.1 Code
D. Using the outlet size of the vent on the appliance and increasing one size for every 50 feet
12. When upgrading to a high-efficiency furnace from a low-efficiency model how is the appliance input
decided?
A. Complete a heat loss calculation
B. Replace the old furnace with the same input
C.
Choose a model that has the same size supply air plenum
D. Choose a modulating furnace with a minimum output equal to 50% of the old furnace input
© 2020 Appliance Technical Institute of Canada
2
UNI T 19
13. Can the vent from a condensing appliance be connected to the B-vent of the appliance it replaces?
A. No, a new vent needs to be installed
B. Yes, if the existing vent is the correct size
C.
Yes, if the existing B-vent is a side-wall termination
D. Yes, if an aluminum liner of the correct size is installed
14. How is vent piping graded for a side-wall installation?
A. Perfectly horizontal
B. Toward the appliance
C.
Away from the appliance
D. To a low point created mid-way in the system
© 2020 Appliance Technical Institute of Canada
3
UNI T 19
Unit 19 – Chapter 02: Servicing of mechanical components
1.
Must a defective heat exchanger in a dwelling unit be replaced immediately?
A. Yes
B. No, it can be temporarily repaired
C.
2.
No, it can be permanently repaired No, only if the CO level is above the maximum acceptable for
the appliance
A high efficiency furnace incorporates how many heat exchangers?
A. One
B. Two, a primary and a tertiary
C.
Two, a primary and a secondary
D. Three
3.
When would a gas technician/fitter use an incline manometer?
A. To check the manifold pressure
B. To complete an external static pressure test
C.
To confirm the operation of the high-limit switch
D. To set the outlet pressure of a line-pressure regulator
4.
What is the purpose of a flame rollout switch?
A. Open in the event of spillage
B. Open when the combustion air is blocked
C.
Protect the burner area from unusually high temperatures
D. Protect the heat exchanger area from unusually high temperatures
5.
What is the purpose of a diaphragm-style pressure switch on a condensing furnace?
A. To confirm the gas pressure is correct
B. To confirm induced draft fan is operating
C.
To confirm the blower assembly is operating
D. To confirm the air supply differential pressure is within limitations
6.
On what type of furnace(s) could you see a combination high-limit/fan control?
A. Low-efficiency only
B. High-efficiency only
C.
Low-efficiency and mid-efficiency
D. Mid-efficiency and high-efficiency
© 2020 Appliance Technical Institute of Canada
4
UNI T 19
7.
What material is recommended for condensate piping after connecting to the appliance?
A. Rigid PVC piping
B. Flexible PVC tubing
C.
Any steel pipe material
D. Any plastic pipe material
8.
How is temperature rise determined?
A. The ambient temperature plus the room air temperature
B. Add the return air temperature to the supply air temperature
C.
Subtract the supply air temperature from the return air temperature
D. Subtract the return air temperature from the supply air temperature
9.
What type of furnace would use a vent damper?
A. Mid-efficiency only
B. Low efficiency only
C.
Low-efficiency and mid-efficiency
D. All types of furnaces use vent dampers in the ducting system
10. What tool should be used to clean the outside of a heat exchanger?
A. Soft brush
B. Wire brush
C.
Sanding block
D. Never clean the outside of a heat exchanger
11. When is a condensate pump required?
A. All condensing appliance installation
B. When a condensate trap cannot be installed
C.
When the condensate cannot drain by gravity to the DWV system
D. When the condensate drain needs to be graded more than ¼ inch per foot
12. Where does condensate form in a condensing appliance system?
A. Only in the primary heat exchanger
B. Only in the secondary heat exchanger
C.
In the primary and secondary heat exchangers
D. In the secondary heat exchanger and the venting system
© 2020 Appliance Technical Institute of Canada
5
UNI T 19
13. How is manifold pressure measured on a residential furnace?
A. Upstream of the combination gas valve with the appliance shut off
B. Downstream of the combination gas valve with the appliance shut off
C.
Upstream of the combination gas valve with the appliance operating
D. Downstream of the combination gas valve with the appliance operating
14. Where is a combustion analysis performed?
A. In the combustion chamber
B. Should be measured after any draft control devices
C.
Should be measured before any draft control devices
D. At the area where the primary and secondary air enters the appliance
© 2020 Appliance Technical Institute of Canada
6
UNI T 19
Unit 19 – Chapter 03: Electrical circuits and components
1.
Referencing a combination control, what is the approximate normal differential setting of the fan
control?
A. 25°F (14°C)
B. 35°F (19°C)
C.
45°F (25°C)
D. 55°F (30°C)
2.
Referencing a mid-efficiency furnace, what causes the fan to shut off under normal operating
conditions?
A. The pressure switch circuit opens
B. The IFC Fan-OFF timer is activated
C.
The fan control cools down enough to open the circuit.
D. The thermostat has reached setpoint temperature and opens the Fan-OFF circuit
3.
On which types of furnaces would you find an auxiliary limit control?
A. Only central furnaces
B. Downflow furnaces only
C.
Horizontal or downflow furnaces
D. Upflow, horizontal, and downflow furnaces
4.
Do all rollout switches have to be manually reset?
A. Yes
B. No
5.
If the return air temperature is 70°F (21°C) and the temperature rise is 75°F (42°C), what is the
supply temperature?
A. 5°F (-15°C)
B. 70°F (21°C)
C.
75°F (24°C)
D. 145°F (63°C)
6.
What component is designed to cause the burner to shut down if there is a blockage in the vent?
A. High-limit
B. Pressuretrol
C.
Roll-out switch
D. Pressure switch
© 2020 Appliance Technical Institute of Canada
7
UNI T 19
7.
What would be the required air flow if a furnace has a rated input of 60,000 Btuh, is 95% efficient,
and the rating plate specifies a temperature rise of 40°- 60°F?
A. 880 CFM
B. 926 CFM
C.
1056 CFM
D. 1,111 CFM
8.
What voltage does the IFC receive from the thermostat circuit on a call for heat?
A. 24 VAC
B. 24 VDC
C.
120 VAC
D. 120 VDC
9.
How is the indoor blower circuit energized on a furnace incorporating an IFC?
A. The IFC uses electronic time delay
B. The IFC uses a temperature-activated switch
C.
The furnace uses a separate fan control board
D. The Fan-ON switch closes in a combination high-limit/fan control
10. What is the range of a typical modulating furnace?
A. Between 0% and 100% of input
B. Between 40% and 100% of input
C.
Between 0% and 100% of capacity
D. Between 40% and 100% of capacity
11. Why is it recommended to perform an ESP after retrofitting a furnace to existing ductwork?
A. To ensure the furnace is operating within the ESP limits
B. To ensure the furnace is operating within the temperature rise limits
C.
To ensure the furnace is operating within the temperature rise limits and the ESP limits
D. To ensure the furnace is operating within the temperature rise limits, the ESP limits, and is not
over-firing
© 2020 Appliance Technical Institute of Canada
8
Answers
Unit 19 – Chapter 01: Forced-air furnaces
1. A
2. C
3. A
4. A
5. D
6. C
7. D
8. C
9. D
10. B
11. A
12. A
13. A
14. B
Unit 19 – Chapter 02: Servicing of mechanical components
1. A
2. C
3. B
4. C
5. B
6. C
7. A
8. D
9. A
10. A
11. C
12. D
13. D
14. C
Unit 18 – Chapter 03: Electrical circuits and components
1. A
2. C
3. C
4. B
5. D
6. D
7. C
8. A
9. A
10. D
11. C
G2 Gas Technician Module 19
1.
Are high-efficiency furnaces power
vented?
Yes
2.
Balancing damper are used to?
Slows the air flow in
the duct and controls
the air flow to each
room
17.
How is a High
efficient furnace
vented?
Can be single or double plastic pipe.
18.
How is a mid
efficient furnace
vented?
Assisted by fan through heat exchanger and naturally through the
venting
3.
Before you start a Newly Installed
Furnace what must be done? What
step is after that?
Measure Gas Pressure
once done Measure
Delta Temperature
19.
How is a natural
draft furnace
vented?
Naturally through a draft hood
4.
Blowers with a belt normally have 1
speed, how is the speed adjusted?
Remove set screws
and rotate the pulley
clockwise to tighten
or counter clockwise
to loosen
20.
How is a pressure
switch tested to
see if it is
defective?
Connect an ohmmeter across the
switch or If the power venter is not
blowing and there is continuity across
the switch, then the switch is faulty and
must be replaced
5.
Burners should be clean when? and
what is used to clean the orfice?
Annually with a
toothpick
21.
6.
Do all rollout switches have to be
manually reset?
No, However most
are automatically
reset
How is Delta
Temperature
measured? and
what should it
match?
Supply Air minus Return Air, It must not
be less or more than Manufacturers
Rating Plate
7.
Does the replacement fan control
have to be the same as the one
being replaced?
Yes
22.
How is Hot Surface
Igniter diagnose?
Connect leads to both wires, check for
voltage and Resistance
23.
8.
The draft gauge measured 0.10'' w.c,
what does this indicate?
Dirty/Blocked AC
Evaporator coil
How is
temperature rise
determined?
Placing thermometer in the return and
supply plenums while the furnace is
running
9.
Duct work system must be properly
sized, what must a gas technician
be aware of?
Air quantities required
and the number and
type of supply outlets
24.
Adjusting the pulleys of the motor
10.
Explain two stage furnace?
Has a low fire and
high fire. Improves
comfort
How is the
delivered air
volume adjusted if
a belt-drive fan
motor is being
used?
Furnace air return runs at 68F, the
blower sends air to heat exchanger
and the temperature increases to
160F. What is our Delta
Temperature?
92F temp rise
25.
How many heat
exchangers does a
conventional
furnace have?
Single heat exchanger
11.
26.
A high efficiency furnace
incorporates how many heat
exchangers?
Two
2 heat exchangers a primary and
secondary
12.
How many heat
exchangers does a
high efficient
furnace have?
How do you calculate Heat loss?
Output/Input
27.
14.
How far does a vent terminate from
a mechanical air supply?
6 ft or greater
How many heat
exchangers do
Natural Draft
Furnace have?
One
13.
15.
How is a belt motor in a furnace
maintained?
Must be Oiled and
Alignment
28.
Every Year
16.
How is a Heat Anticipatory
selected?
Based on Amperage
Draw
How often should
a thermostat be
cleaned?
29.
How tall are low boys and where
would you install them?
Approximately 4 feet
high and primarily
installed in basements
with low head room.
If a category 3 appliance is
equipped with a electrically
operated automatic vent damper
when would it operate?
When the damper is
proven to be fully open
before ignition of the
main burner.
31.
If a gas valve is working properly
but a humming sound is heard the
probable cause is?
Low secondary voltage
32.
If the combustion air supply on a
high efficient furnace is blocked
what component would disable
it?
Pressure switch
33.
If the return air temperature is
70F and the temperature rise is
75F what is the supply
temperature?
145F
34.
If the venting on a high efficiency
furnace runs through unheated
spaces, what must be done?
Insulate piping to
prevent Condensation
and freezing
35.
If you read 24V on the gas meter
and the Valve doesn't open what
could be wrong?
The Valve is faulty and
must be replaced
In a high efficiency furnace, which
heat exchanger does the Supply
air pass through first?
The Secondary
In the event no sewer drain is
present how is condensation
water mitigated?
A Condensation Pump
38.
Is a fan necessary to move the
flue gases through a gravity vent?
Why?
No, hot air rises.
39.
The Main circuit board on a
furnace is 120V, to connect a
Accessory what must be done?
A step down
Transformer 24V must
be use to match the
accessory.
40.
Most heat exchangers are made
of?
Stainless Steel,
Aluminized Steel,
Vitreous Enamel
41.
Must all defective heat
exchangers be replaced
immediately?
Yes
42.
On a category 1 appliance the
high limit is always wired in series
with what?
Gas valve
30.
36.
37.
43.
On a forced draft burner,
where is the fan located?
Upstream from the
combustion chamber.
44.
On a furnace with an
integrated control board
what controls the blower
motor?
Timer Relay
45.
On a furnace with no filter
rack, what should be done?
Rack should be built on return
duct connection
46.
Once a fan motor has been
cleaned what are the next
two steps?
Check electrical wire for
tighteness and clean the
blower components
47.
Once the furnace is
installed, what are the gas
technician's responsibilities
to the user?
To instruct the the user in the
safe and correct operation of
all appliances and equipment
- clause 4.3.2
48.
On which types of furnaces
would you find an auxiliary
limit control?
Down Flow an Horizontal
Furnaces
49.
A Tee is required to be
installed off the PVC 636
pipe, what is the
component that should be
attached?
A Neutralizer with a hose
leading to the drain trap
50.
The top of a plenum should
have what minimum
clearance to combustibles?
1 " or 25 mm
51.
Typical Draft gauge
reading should be
between?
0.02 to 0.16 inches w.c
52.
What are power venters
used for?
Extra-long vents, Excessive
negative pressure, improper
vent designs, and safe reliable
solution for venting problems
53.
What are the 4 types of
war air furnaces?
1. Upflow (high boy)
2. Down Flow or Counter
Flow
3. Horizontal
4. Low Boy
54.
What are the different
types of gas valves?
Single stage, 2 stage and
modulating
55.
What are the flue gas
temperatures on a natural
draft furnace?
250 F - 350 F
56.
What are the possible
causes of abnormal Static
Pressure results?
Dirty Air Filters andBlocked
AC Evaporator Coil
57.
What causes the fan to
shut off under normal
operating conditions?
The warp switch inside the fan
control cools down enough to
open the circuit to the fan
58.
What controls the
operation of a two
stage furnace?
Two stage thermostat
What does a high
efficient furnace do
that natural draft and
mid efficient dont?
It condenses
What do you call the
two heat exchangers in
a high efficient
furnace?
Primary and secondary
What efficiency does a
high efficient furnace
operate at?
90%+
What flue gas
temperatures does a
High efficient furnace
have?
80 F - 120 F
63.
What is a plenum?
Duct work system connected
directly to the furnace
64.
What is condensate
drain piping used for?
Dispose Liquid waste
65.
What is Static Pressure
in a furnace?, how is it
measured?, and what
standard must it meet?
The difference in Return and
Supply Air pressure. It's measured
with a Draft Gauge. It must meet
Manufacturers Rating plate
standard
66.
What is the AFUE rating
of a typical medium
efficiency furnace?
67.
68.
59.
60.
61.
62.
69.
70.
71.
What is the difference in a mid
efficient furnaces heat
exchanger compared to a
natural draft one?
Mid efficient is more
restrictive
72.
What is the disadvantage of
oversizing a furnace?
Inefficiency
73.
What is the formula for
Calculating CFM?
BTUH (output)/ (1.1 x
Temp difference)
74.
What is the high limit switch
safety temperature?
200F
75.
What is the max efficiency of a
Mid efficient furnace?
80 %
76.
What is the normal differential
setting on a fan control? Can
this setting be adjusted?
Yes 25 F
77.
What is the purpose of the Heat
Anticipator?
Senses temperature
faster than thermostat
and reduces the cycle by
10 minutes
78.
What is used to clean outside
and inside a heat exchanger?
Soft paint brush is used
outside and wire brush is
used for Corrosion build
up
79.
What kind of efficiency does a
natural draft furnace have?
Max 70%
80.
What kind of ignition source is in
a High efficient furnace?
HSI/Spark
81.
What kind of pilot does a mid
efficient furnace have?
Intermittent pilot
78% - 82%
82.
What methods would you use to
determine if a heat exchanger is
cracked?
Smoke, visual inspection
and flue gas analysis
What is the average
CFM per ton of a heat
pump?
450 CFM
83.
What must a fan motor be
capable of?
Capable of rotating on
full capacity at start
84.
400 cfm per ton
What must a Gas technician do
before sizing or replacing a
furnace?
A Heat loss calculation
What is the average
CFM per ton of an air
conditioner
85.
What is the benefit of
the secondary heat
exchanger being
heated first?
It prolongs the life of the Primary
heat exchanger
What must the return plenum on
a furnace be able to do?
Withstand negative air
pressure
86.
What must the supply plenum on
a furnace be able to do?
Handle the maximum
operating pressure of the
furnace
What is the big
differences between
the different types of
gas valves?
You get more comfort for the
home owner. The least
comfortable being the single
stage and the most being the
modulating gas valve.
87.
What proves that your Induce
blower is functional?
The pressure switch
88.
What purpose does a
Automatic damper serve? How
does it work?
Reduce heat loss up the
chimney and it opens
when burners fire and
closes during the off
cycle
What should be done if a
customer shows signs of Co
poisoning?
Evacuate, Shut off
appliance, Call TSSA
90.
What temperature are mid
efficient furnaces flue gases?
250 F
91.
What tool should be used to
clean the outside of the heat
exchanger?
Soft Brush
92.
What type of furnace is used in
areas of limited head room?
Horizontal Forced Air
93.
What type of pilot does a
natural draft furnace have?
Standing
94.
What voltage usually operates
the control module?
120V
95.
What will cause the burner to
shut down if there is a blockage
in the vent?
Vent outlet Pressure
Switch
96.
When attaching a Supply
plenum to a furnace which
"Cleat is used? and how is it
installed?
S Cleat and the V is
faced outside on the
Furnace
97.
When connecting the
rectangle duct, which cleat is
used on the longest area? and
which is used on the shortest?
S cleat on the longest
and D cleat on the
shortest
98.
When is a blower cooling relay
used?
Combined heating and
cooling operation
99.
Where do the condensate lines
for a category 4 furnace run
to?
An open drain
100.
Where do you put your gauges
when measuring temp rise?
Out of sight of the heat
exchanger. Radiant heat
can give higher readings
101.
Where do you usually install a
horizontal furnace?
Positioned on its side
usually in a crawl space
or suspended from floor
joists in basement.
102.
Where is the Automatic
Damper located?
Down stream of the draft
hood
103.
Where is the return air and
supply air on a low boy
furnace?
Both are on the top
89.
104.
Where is the supply and return on
a Down Flow Furnace?
Supply air is through
the bottom and return
air is through the top
105.
Where is the supply and return on
an Upflow Furnace?
Supply is on the top
and return air is near
bottom
106.
Where must a furnace air filter be
located and which direction?
Arrow must face the
negative pressure side
of the Fan
107.
Which category of furnace is
standard atmospheric appliance?
Category 1
108.
Which furnace type is the most
popular?
High boy Up Flow
109.
Which two documents must be
adhered to if you replace a fan
control?
Manufacturers
Specifications and the
Electrical Code
110.
Which Vent is the most heat
resistant?
Type A
111.
Your pressure switch is working,
but the induce blower keeps
shutting off, what is the cause?
Blockage in Venting
system
Module 20
Hydronic Heating
Systems
© 2020 Appliance Technical Institute of Canada
UNI T 20
Unit 20 – Chapter 01: Boiler
1.
What prevents the water in a hydronic heating system from boiling into steam when the system is
operating above the atmospheric boiling temperature?
A. Natural convection
B. Make-up water is added
C.
Pressurization of the system
D. Constant circulation
2.
Which of the following would be considered part of a hydronic control system?
A. Boiler
B. Circulator
C.
Radiator
D. Aquastat
3.
What is installed to protect potable water connections to a boiler (make up water connections) from
cross-contamination with non-potable boiler water or toxic substances?
A. Backflow preventer
B. Relief valve
C.
Aquastat
D. Low water cut off
4.
What is not an advantage of a hydronic heating system?
A. Fast reaction time
B. Quiet operation
C.
Increased comfort
D. Less air stratification
5.
What input would require a low water cut off for a hot water boiler?
A. 500 MBtu/h
B. 300 MBtu/h
C.
120 MBtu/h
D. 75 MBtu/h
6.
What is used to connect multiple cast-iron boiler sections together into a boiler block assembly?
A. Soldered couplings
B. Threaded unions
C.
Tapered push-nipples
D. Raised face flanges
© 2020 Appliance Technical Institute of Canada
1
UNI T 20
7.
Which type of boiler could be used to directly heat domestic water?
A. Steel water-tube
B. Copper fin-tube
C.
Cast-iron sectional
D. Steel fire-tube
8.
What is the result if flue gas combustion products are cooled below their dew point?
A. Cavitation
B. Condensation
C.
Stratification
D. Concentration
9.
Steel water tube boilers are commonly used for the production of hot water or steam.
A. True
B. False
10. To prevent thermal stress damage, this type of boiler requires constant water circulation during
firing.
A. Steel fire-tube
B. Cast-iron sectional
C.
Copper fin-tube
D. Steel water-tube
11. Condensing boiler are typically made from what material?
A. Cast-iron
B. Stainless steel
C.
Copper
D. Carbon steel
12. For atmospheric boilers, what is the term used to explain the result if there is no draft, a backdraft, or
a blockage in the venting system beyond the draft hood?
A. Leakage
B. Spillage
C.
Discharge
D. Emission
13. What does an automatic vent damper actuator have to control the boiler’s burner?
A. Proving switch
B. Igniter
C.
Transformer
D. Circulator
© 2020 Appliance Technical Institute of Canada
2
UNI T 20
Unit 20 – Chapter 02: Distribution and control systems
1.
What is the simplest type of hydronic distribution system?
A. Reverse-return
B. Direct-return
C.
Series loop
D. Monoflo
2.
Which two-pipe heating system is easiest to balance?
A. Reverse-return
B. Direct-return
C.
Series loop
D. Monoflo
3.
Which hydronic distribution system uses diverter tees to help direct main water flow through the
heating unit?
A. Reverse-return
B. Direct-return
C.
Series loop
D. Monoflo
4.
Which hydronic distribution system is known as first-fed, first-return ?
A. Reverse-return
B. Direct-return
C.
Series loop
D. Monoflo
5.
What device within a closed hydronic system accommodates for the volumetric change of the system
fluid under normal operating conditions?
A. Expansion tank
B. Relief valve
C.
Air separator
D. High limit aquastat
6.
Which device within a hydronic heating system is required to release water during an unsafe
condition caused by excessive pressures?
A. Expansion tank
B. Relief valve
C.
Air separator
D. High limit aquastat
© 2020 Appliance Technical Institute of Canada
3
UNI T 20
7.
Which type of valve is best suited for throttling flow?
A. Gate valve
B. Globe valve
C.
Check valve
D. Relief valve
8.
A thermostatic radiator valve can be operated by mechanical or electric drive head.
A. True
B. False
9.
What side of a structure should an outdoor air temperature sensor be placed?
A. North
B. South
C.
East
D. West
10. What is the purpose of a balancing valve?
A. Increase flow
B. Isolate flow
C.
Equalize flow
D. Stop reverse flow
11. What is installed in a system to ensure continuous flow in the system, no matter how many zone
valves are open or closed?
A. Four-way mixing point
B. Differential pressure bypass
C.
Outdoor air sensor
D. Flo check valves
12. This device is normally wired in series with an operating aquastat so that either one can shut off the
burner.
A. Bypass limit
B. High limit
C.
Low limit
D. No limit
© 2020 Appliance Technical Institute of Canada
4
UNI T 20
13. What can be used to sense problems in the flow of combustion products (like flue blockages)?
A. Rollout switch
B. Flow switch
C.
Low water switch
D. Proving switch
14. What valve is used to prevent reverse flow in a piping system?
A. Gate valve
B. Globe valve
C.
Check valve
D. Relief valve
15. What can be used to provide hydraulic separation in a primary secondary hydronic distribution
system?
A. Monoflo tees
B. Closely-spaced tees
C.
Diversion tees
D. Oversized tees
© 2020 Appliance Technical Institute of Canada
5
UNI T 20
Unit 20 – Chapter 03: Circulators
1.
What is the name for the point where the expansion tank is attached to the system piping?
A. Point of no point
B. Point of view
C.
Point of no pressure change
D. Point of no return
2.
Immediately upstream of the expansion tank is the best place to install a primary circulating pump in
a hydronic system.
A. True
B. False
3.
What is the rotating piece of a centrifugal pump called?
A. Impeller
B. Propeller
C.
Volute
D. Rotor
4.
What is the effect when increasing the RPM of a centrifugal pump?
A. More pressure and more flow
B. Less flow
C.
More flow
D. More pressure
5.
Where is the area of lowest pressure within a centrifugal circulator?
A. Impeller eye
B. Volute
C.
Outlet port
D. Pump body
6.
The pressure difference a pump can produce between its inlet and outlet ports is a definition of
which of the following?
A. Flow rate
B. Velocity
C.
Head
D. Drift
© 2020 Appliance Technical Institute of Canada
6
UNI T 20
7.
How many USGPM would be required to supply 40,000 Btuh, if the design temperature drop for the
system is 30°F?
A. 3.75 USGPM
B. 2.67 USGPM
C.
5 USGPM
D. 4 USGPM
8.
What is the effect of installing two centrifugal pumps in series?
A. 50% more pressure
B. Half the flow
C.
Double the flow
D. Double the pressure
9.
What is the effect when a shut off valve is closed downstream of a centrifugal circulator?
A. Current draw decreases
B. Current draw increases
C.
Voltage increases
D. Voltage decreases
© 2020 Appliance Technical Institute of Canada
7
UNI T 20
Unit 20 – Chapter 04: Hydronic control system servicing and maintenance
1.
What is the typical system design pressure for a residential hydronic boiler?
A. 50 60 psig
B. 20 28 psig
C.
12 15 psig
D. 32 45 psig
2.
What should be checked first if the boiler’s system pressure is higher than normal?
A. Expansion tank
B. Relief valve
C.
LWCO
D. PRV
3.
How can a technician increase a hydronic system’s static pressure setting?
A. Turn the PRV adjustment clockwise
B. Turn the PRV adjustment counter-clockwise
C.
Open the relief valve
D. Open the boiler drain
4.
You tell if a differential pressure bypass valve is working correctly if the pressure at the discharge
side of the pump does not increase when zone valves close.
A. True
B. False
5.
If a boiler’s burner will not fire, which of the following should be checked first?
A. Aquastats
B. Water supply
C.
Venting system
D. Air vents
6.
What is the likely cause of incomplete combustion and high flue stack temperatures?
A. Air in the system
B. Low water condition
C.
Over-firing the burner
D. High water pressure
© 2020 Appliance Technical Institute of Canada
8
UNI T 20
7.
Air in the system can create what common problem?
A. Noise
B. High velocities
C.
Condensation
D. High flue temperatures
8.
Who can test a backflow preventer?
A. Certified tester
B. Gas technician
C.
Homeowner
D. Plumber
9.
If the pressure in a hydronic system increases immediately after the burner comes on, what is the
cause?
A. Expansion tank is water-logged
B. Relief valve is faulty
C.
PRV is faulty
D. Gas pressure is too low
10. What happens if a zone valve’s end switch fails to close?
A. Thermostat will open
B. Pump will not shut off
C.
Burner will not fire
D. PRV will open
11. A customer complains that there is no heat in the top floor of a hydronic heating system. What is the
most likely cause?
A. Zone valve is stuck open
B. Air lock in system
C.
Pump is oversized
D. Static pressure too high
12. What should be observed to avoid pump cavitation?
A. Install straight piping upstream
B. Keep fluid temperature low as possible
C.
Keep static pressure high as possible
D. All of the above
© 2020 Appliance Technical Institute of Canada
9
UNI T 20
Unit 20 – Chapter 05: Pool heating systems
1.
What is the purpose of the lint trap/strainer in a pool system?
A. Prevents reverse flow into the pool
B. Equalize flow in the system
C.
To protect the pump
D. Heats the pool water
2.
What must be done to remove accumulated debris in a sand filter?
A. Nothing is done
B. The filter must be replaced
C.
Change the sand
D. Backwashing
3.
What is the normal differential setting for a pool heater’s pressure switch?
A. 2 psig
B. 14 psig
C.
0.5 psig
D. 10 psig
4.
What is the function of a pool heater’s pressure switch?
A. Protects the boiler from damage
B. Helps to keep the water clean
C.
Senses the water level in the pool
D. Turns on the make-up water system
5.
What is the maximum setting for a pool boiler’s operating aquastat?
A. 100°F
B. 140°F
C.
160°F
D. 180°F
6.
What is the maximum setting for a pool boiler’s high limit aquastat?
A. 100°F
B. 140°F
C.
160°F
D. 180°F
© 2020 Appliance Technical Institute of Canada
10
UNI T 20
7.
What is used when attempting to chemically clean the inside surfaces of a pool boiler’s heat
exchanger tubes?
A. Soap and water
B. Muriatic acid
C.
White vinegar
D. Soda-ash
8.
What is the recommended flow rate for high-rate sand that is used for a pool filter?
A. 0.5 -1 USGPM
B. 1 -2 USGPM
C.
3 -5 USGPM
D. 15 - 20 USGPM
9.
When the flow rate through a pool system is greater than 125 USGPM, what is required between the
heater’s inlet and outlet pipes?
A. Manual bypass
B. Automatic compensator
C.
Backup heater
D. Check valve
10. Where shall chlorine be added to the pool’s circulating system?
A. Upstream of the pump
B. Downstream of the skimmer
C.
Downstream of the heater
D. Upstream of the filter
© 2020 Appliance Technical Institute of Canada
11
Answers
Unit 20 – Chapter 01: Boiler
1. C
2. D
3. A
4. A
5. A
6. C
7. B
8. B
9. A
10. C
11. B
12. B
13. A
Unit 20 – Chapter 02: Distribution and control systems
1. C
2. A
3. D
4. B
5. A
6. B
7. B
8. A
9. A
10. C
11. B
12. B
13. A
14. C
15. B
Unit 20 – Chapter 03: Circulators
1. C
2. B
3. A
4. A
5. A
6. C
7. B
8. D
9. A
Unit 20 – Chapter 04: Hydronic control system servicing and maintenance
1. C
2. D
3. A
4. A
5. A
6. C
7. A
8. A
9. A
10.C
11.B
12.D
Unit 20 – Chapter 04: Hydronic control system servicing and maintenance
1. C
2. D
3. A
4. A
5. A
6. B
7. B
8. D
9. A
10. C
© 2020 Appliance Technical Institute of Canada
2
G2 Gas Technician Module 20
1.
Above what input is a low
water cut-off a required
component of a hot water
boiler?
400,000 BTU
16.
Is it acceptable to leave water in
the heater when the system is
winterized? and why?
No because of
Freezing, Expansion,
Splitting Pipes,
Damaging Equipment
2.
Air in the system or low flue
gas temperature can cause
what?
Corrosion
17.
The limit is set below system
design temperature what
happens?
3.
Can the installation of air
vents help prevent pump
cavitation?
Yes
Boiler fires but cycles
on/off limit control and
insufficient heat
throughout building
18.
4.
Circulator making loud rattling
noise.
Pump cavitation, broken
pump coupler
List four common air elimination
devices used on hydronic heating
system.
Manual Air Vent,
Automatic Air vent, Air
purgers, and
Microbubblers
5.
The flow switch keeps boiler
burner from firing but
activates when shaken why?
Incorrect Installation, Pump
size and Flow switch
sensing paddles
19.
List the four subsystems of a
hydronic space heating system?
6.
Gurgling sound in pipes,
cause? and how to fix?
Air Bubbles, you should
shut down the pump and
bleed all radiators
Heat Source,
Circulation system,
Heat Emitters, Control
system
20.
No
7.
How is an automatic vent
damper interlocked to ensure
it is in the open position
before the burner can fire?
The damper actuator has a
proving switch that is
interlocked with the
thermostat controlling the
burner
May chemical additives be
introduced into a combustion
system?
21.
On three and four-way mixing
valves, where does the mixing
take place?
Within the valve body
22.
Operated by thermostat. Opens
water flow and activates burner
and pump with it's end switch.
Zone control valve
23.
The pressure difference produced
by a pump between it's inlet and
outlet ports is a partial definition
of what?
Pump Head
24.
Thermal actuated dampers
operate in response to?
Temperature of the flue
gases
25.
What are the three general
methods used to control
temperature zones in a building?
Circulating pumps,
zone valves, and
thermostatic radiator
valves
26.
What can be done to correct
overfiring?
Manifold Pressure
should be checked and
adjusted or check
burner orifice size
27.
What causes no heat in upper
floor of a building?
Air in the system due to
problem with water
feed regulator
8.
How is an immersion-type low
water cut-off tested?
By draining the system,
same as Float Type
9.
How should galvanized pipe
and copper be joined
together?
Dielectric Insulation Fittings
10.
If a check valve chatters, what
must be done?
Must be replaced
11.
If the filter pump is not
running, will the pressure
switch allow the heater to
fire?
No
12.
If two identical pumps are
installed in series, what
happens to the system
pressure?
Pressure Increases
13.
In a hydronic heating system,
air can cause what three
problems?
Corrosion, Insufficient heat
output and noise in the
system
14.
Incomplete combustion and
very high stack temperature
may indicate what?
Over Firing
15.
Insufficient heat output is
generally a result of?
Insufficient or no flow in the
system and incorrect
temperature settings
28.
What device within a closed hydronic
system is required to provide provision for
the volumetric expansion of the system
fluid under normal operating condition?
Expansion
Tank
29.
What forces of nature have effects on pool
heating?
Direct
sunlight, wind,
shade from
trees and
structures
30.
What happens if the same pumps are
installed in parallel?
GPM
Increases
31.
What happens to the water vapour in the
combustion products if the flue gases are
cooled below the dew point?
The water
vapour
condenses
into liquid
state
32.
What is the only recommended procedure
for cleaning heat exchanger tubes that
does not require removal of the heat
exchanger?
Wire Brush
33.
What is the primary cause of sooting on
heat source surfaces?
Flame
impingment
34.
What is the purpose of a balancing valve?
Modulate and
balance the
flow through
each branch
35.
What must be done to protect the potable
water supply to a hot water boiler?
Approved
backflow
preventer
installed in
the water
supply
36.
What prevents the water in a hydronic
heating system from boiling into steam
when the system is operating above the
atmospheric temperature?
Pressurization
of the system
37.
What reduces the pressure of incoming
water coming into the boiler through a
domestic water distribution pipe?
Pressure
reducing
valve and
boiler feed
water valve
38.
What two purposes are served when a
combination system is used?
Space
Heating and
Domestic
Water
39.
What two types of drive heads can be used
on a thermostatic radiator valve?
Mechanical
and electrical
40.
Where is the circulating pump in a
hydronic system located?
In the supply main,
just downstream of the
Expansion Tank
41.
Where must chlorine be injected
into the pool circulating system?
Down stream of the
heater
42.
Where should an outdoor
temperature sensor be placed?
Away from direct
sunlight, away from
other heat sources and
away from a shielding
structure
43.
Which device within a hydronic
heating system is required to
release water during an unsafe
condition caused by excessive
pressures?
ASME Pressure Relief
Valve
44.
Which is the simplest hydronic
distribution system?
Single Series Circuit
45.
Which pool component is most
likely to corrode? and why?
Heat exchanger and
burner because of
chemicals, ph, salt and
condensation.
46.
Which type of valve is best suited
for throttling flow?
Globe Valve
47.
Why are cast-iron sectional boilers
used only in closed loop hydronic
system?
Purge itself of Air and
reduces corrosion
48.
Why does a copper fin-tube boiler
require less surface area to
transfer heat than a steel fire tube
boiler?
Copper Tube has a
higher thermal
conductivity than steel
tube
Module 21
Space Heaters &
Fireplaces
© 2020 Appliance Technical Institute of Canada
UNI T 21
Unit 21 – Chapter 01: Space heaters
1.
For a millivolt control system, select the thermostat wire gauge that will enable the farthest distance
between the thermostat and the heater?
A. 14 GA
B. 16 GA
C.
18 GA
D. 20 GA
2.
Space heaters installed in a bathroom must be of the direct-vent type.
A. True
B. False
3.
At approximately what distance from the floor should a thermostat be located?
A. 100 cm
B. 125 cm
C.
150 cm
D. 200cm
4.
How often should a space heater have a maintenance inspection?
A. Minimum monthly
B. Minimum annually
C.
Minimum every 5 years
D. Never these unit are maintenance free
5.
Where is the draft relief opening typically located on a room heater?
A. On top of the unit
B. On the side of the unit
C.
At the lower front of the unit
D. Under the draft hood at the back of the unit
6.
What is the purpose of a reversible draft diverter on a gas room heater?
A. To connect a power vent
B. To connect unit to a direct vent kit
C.
Enable unit to be used as an unvented heater
D. To enable a horizontal vent connection to the unit
© 2020 Appliance Technical Institute of Canada
1
UNI T 21
7.
Which type of control valve will provide an infinite number of firing rates between low fire and high
fire?
A. Manual control valve
B. Two stage control valve
C.
Modulating control valve
D. Single-stage control valve
8.
What type of unit heater produces low pressure, high volume flow?
A. Blower type
B. Axial fan type
C.
Counterflow type
D. Low intensity type
9.
Which type of wall furnace will reduce heat stratification in a room?
A. Blower type
B. Axial fan type
C.
Counterflow type
D. Low intensity type
10. Which type of vent is used in a conventional wall furnace?
A. B vent
B. C vent
C.
BH vent
D. BW vent
11. What type of thermostat is required for a fully modulating unit heater?
A. Millivolt thermostat
B. Two stage thermostat
C.
Modulating thermostat
D. Single stage thermostat
12. A wall furnace can be installed directly on a wood floor.
A. True
B. False
13. A ba eboard hea er elec rical
ppl ma be pl gged direc l in o a all recep acle
A. True
B. False
© 2020 Appliance Technical Institute of Canada
2
UNI T 21
14. Direct vent wall furnaces are only available as natural convection units.
A. True
B. False
15. There are 3 heaters, each with a 0.25 amp control circuit all being control by one thermostat. What
should the amperage setting be for a thermostat with an anticipator?
A. 0.25 amps
B. 0.50 amps
C.
0.75 amps
D. amps
16. What component directs the heat from a low-intensity infrared heater onto the floor?
A. Fan
B. Reflector
C.
Ceramic mat
D. Radiant tube
17. What temperature level may be reached with a high-intensity infrared heater?
A. 6500C
B. 9800C
C.
12000C
D. 18000C
18. All infrared heaters are vented.
A. True
B. False
19. How are the outside surfaces of the reflector cleaned?
A. Steel wool
B. Damp cloth
C.
Wire brush
D. Power washer
20. The combustion products of a construction heater are vented into the heated area.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
3
UNI T 21
21. What type of construction heater would be used for applications that call for clean air, free from
moisture and contaminated fumes?
A. Blower
B. Radiant
C.
Natural gas
D. Indirect fired
22. What component is designed to stop the flow of gas when the heater is accidentally knocked over?
A. Piezo switch
B. Off-level switch
C.
Tip-over switch
D. High-limit switch
© 2020 Appliance Technical Institute of Canada
4
UNI T 21
Unit 21 – Chapter 02: Fireplaces
1.
What are the two categories of gas fireplaces identified by the Canadian Energy Efficiency
Regulation?
A. Gas fireplace inserts and gas stoves
B. Zero-clearance gas fireplaces and gas logs
C.
Decorative gas fireplaces and heating gas fireplaces
D. Vent free gas fireplace and decorative appliances
2.
What type of gas fireplace is used to convert an existing wood burning masonry chimney to gas?
A. Insert
B. Power vented
C.
Free-standing
D. Zero-clearance
3.
What type of gas fireplace is used on a new home installation and surrounded by framing?
A. Insert
B. Power vented
C.
Free-standing
D. Zero-clearance
4.
What is the minimum FE rating for heating gas fireplaces?
A. 50%
B. 75%
C.
90%
D. There is no minimum efficiency requirement
5.
What must be done with the damper when installing a gas log set into a vented wood burning
fireplace?
A. Throttled as needed
B. Locked in fully open position
C.
Locked in fully closed position
D. Operating handle modified for accessibility
6.
What type of direct vent uses to completely separate pipes?
A. Coaxial
B. Collinear
C.
Power
D. Natural
© 2020 Appliance Technical Institute of Canada
5
UNI T 21
7.
What type of glass is used on a gas fireplace?
A. Tinted
B. Ceramic
C.
Annealed
D. Laminated
8.
How is the blower controlled in a gas fireplace?
A. Thermopile
B. Pressure switch
C.
Wall thermostat
D. Temperature sensitive switch
9.
Besides lighting the main burner, what purpose does a standing pilot have?
A. Preheats the chimney flue
B. Energizes the millivolt control circuit
C.
Completes the flame rod sensing circuit
D. Heats the bulb of the thermostatic switch
10. What type of venting system enables units to be installed with longer horizontal vent runs?
A. Coaxial
B. Collinear
C.
Power
D. Natural
11. Air Duct kits may be installed onto any gas fireplace.
A. True
B. False
12. Modern intermittent pilot fireplaces control circuits operate on what voltage?
A. 6 VDC
B. 24 VAC
C.
120VAC
D. 750 millivolts
© 2020 Appliance Technical Institute of Canada
6
Answers
Unit 21 – Chapter 01: Space Heaters
1. A
2. A
3. C
4. B
5. D
6. D
7. C
8. B
9. C
10. D
11. C
12. A
13. A
14. B
15. C
16. B
17. D
18. B
19. B
20. A
21. D
22. C
Unit 21 – Chapter 02: Fireplaces
1. C
2. A
3. D
4. A
5. B
6. B
7. B
8. D
9. B
10. C
11. B
12. A
G2 Gas Technician Module 21
1.
A broken or cracked
ceramic tile is causing
flash back what must be
done?
Replace cracked or broken
ceramic tile
2.
BW vent shall only be
used with a?
Recessed wall furnace
3.
Construction heaters are
allowed for permanent
heating.
No they are designed for
temporary heating
4.
Decorative appliances
installed in a room shall
be?
Direct Vent
5.
Flash back is occurring
due to improper sealing
of ceramic tile to burner
body caused by
breakdown of gasket
material
6.
7.
8.
9.
10.
11.
Mainenance of a high
intensity infrared
heater. Cleaning the
tile? The burner
head? Reflectors?
Clean ceramic tile with compressed
air, avoid directing at gasket material
between tile and heater body and do
not exceed 20 psi.
Clean the burner head with
compressed air not exceeding 60
psi. Blow through venturi towards
atmosphere then blow back the
other direction but avoid forcing dust
back through venturi by directing air
flow.
Clean reflectors with a soft cloth and
mild soap solution.
Contact the heater distributor
12.
A room heater
installed in either in a
room with sleeping
accommodations are
provided or in a
public area shall
Have a 100% safety shut off control
How does a decorative
fire place work?
Ceramic logs placed over a
bar-type burner gives the
illusion of an open fire.
13.
Low gas pressure, plugged burner
tiles and faulty tile gasket
How does a low intensity
infrared heater work?
Gas burner fires into mouth of
tube and hot flue gases travel
through tube. It emits infrared
heat which is directed by
reflector suspended above the
tube.
Three causes of
flashback on a high
intensity infrared
heater?
14.
5000 ppm
How far shall a swimming
pool heater be installed
from the property line?
18" clause - 7.26.3
Unvented type
infrared heaters that
have mechanical
ventilation shall
maintain a cabon
dioxied level which is
less than?
15.
Improper pressure
entering the venturi tube
causing flashback what
should be done?
Check burner gas pressure.
What are high
intensity infrared
heaters made of?
Porous ceramic, drilled port
cermaics, stainless steel or a
metallic screen.
16.
Tube burner, Box burner and
Ceramic Tile burner
Is a decorative appliance
approved for installation
in a bedroom?
Yes, if it is direct vented. clause 7.25.4
What are the three
types of burners in a
decorative
appliance?
17.
What is the max
length of a metal
connector supplying
gas to a suspended
infrared heater?
2 ft
18.
What temp does a
high intensity
infrared heater
operate at?
1800 F
19.
What temperature does a low-intensity infrared heater fire at?
where are they used?
1200 F and are used in factories and commercial buildings
20.
What type of flame are decorative appliance designed to make?
Luminous flames
21.
What type of heat transfer is typical with a wall furnace? (recessed
heater)
Convection
22.
What type of vent is used on a wall furnace?
BW Venting
23.
When a construction heater is in full operation what must it have?
Adequate air supply
24.
When installing a gas log set into an existing fireplace what must be
done?
Permanently secure the damper into the open position.
clause 7.25.5
25.
Where are fireplace inserts designed for?
They are designed to fit into an existing masonry or
factory-built fireplace
26.
Where cant you install an unvented infrared heater?
Residential, care or detention facilities. clause 7.23.1(c)
27.
Where can you never use a construction heater?
Inhabited homes, inhabited parts of a building or in a
recreational vehicle
Module 22
Venting Practices
© 2020 Appliance Technical Institute of Canada
UNI T 22
Unit 22 – Chapter 01: Venting systems
1.
What is a forced draft?
A. Draft produces by mechanical device downstream from the combustion zone.
B. Draft produces by mechanical device upstream from the combustion zone.
C.
Draft produces by the upward movement of hot gases, creating a negative pressure.
D. A condition in which a draft is forced downward and can cause flue gas spillage.
2.
What is an induced draft?
A. Draft produces by mechanical device downstream from the combustion zone.
B. Draft produces by mechanical device upstream from the combustion zone.
C.
Draft produces by the upward movement of hot gases, creating a negative pressure.
D. A condition in which a draft is forced downward and can cause flue gas spillage.
3.
What is a down draft?
A. Draft produces by mechanical device downstream from the combustion zone.
B. Draft produces by mechanical device upstream from the combustion zone.
C.
Draft produces by the upward movement of hot gases, creating a negative pressure.
D. A condition in which a draft is forced downward and can cause flue gas spillage.
4.
What is a natural draft?
A. Draft produces by mechanical device downstream from the combustion zone.
B. Draft produces by mechanical device upstream from the combustion zone.
C.
Draft produce by the upward movement of hot gases creating a negative pressure.
D. A condition in which a draft is forced downward and can cause flue gas spillage.
5.
Select the simplified imperial formula used to calculate theoretical draft.
A. 𝐷
.0
B. 𝐷
7.6
C.
3450
𝐷
D. 𝐷
6.
∆
∆
𝐻
𝐻
500
What combination will give the greatest draft?
A. Lowest stack temperature, highest outdoor air temperature and shortest vent.
B. Highest stack temperature, lowest outdoor air temperature and highest vent.
C.
Highest stack temperature, highest outdoor air temperature and highest vent.
D. Lowest stack temperature, lowest outdoor air temperature and lowest vent.
© 2020 Appliance Technical Institute of Canada
1
UNI T 22
7.
The average stack temperature is the average between the temperature at the flue collar and the
temperature at the vent termination.
A. True
B. False
8.
To extract heat from flue gases, what would be installed?
A. A condenser
B. A heat reclaimer
C.
A heat exchanger
D. Heat recovery unit
9.
Each vent system has a maximum capacity related to flow and a minimum capacity related to
temperature.
A. True
B. False
10. There is no limit to the benefits gained by increasing the vent height.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
2
UNI T 22
Unit 22 – Chapter 02: Vent installation and assembly
1.
Which vent type is capable of withstanding the highest flue gas temperature?
A. Type A vent
B. Type B vent
C.
Type C vent
D. Type L vent
2.
What is the maximum input of an appliance being vented through an exhaust canopy?
A. 12 kW
B. 40 kW
C.
120 kW
D. 400 kW
3.
How are the joints on a C-vent secured?
A. Gear clamps
B. Three screws
C.
Locking bands
D. Solvent cement
4.
How are the joints on a BH Class II, A and B temperature rated, vents secured?
A. Gear clamps
B. Three screws
C.
Locking bands
D. Solvent cement
5.
How are the joints on a BH Class II, C temperature rated, vents secured?
A. Gear clamps
B. Three screws
C.
Locking bands
D. Solvent cement
6.
How are the joints on a BH Class II, D temperature rated, vents secured?
A. Gear clamps
B. Three screws
C.
Locking bands
D. Solvent cement
© 2020 Appliance Technical Institute of Canada
3
UNI T 22
7.
What type of vent is used with a recessed wall furnace?
A. Type B vent
B. Type L vent
C.
Type BH vent
D. Type BW vent
8.
What is the maximum vent gas temperature for Type L vents?
A. 90°C (195°F)
B. 110°C (230°F)
C.
243°C (470°F)
D. 288°C (550°F)
9.
What is the maximum vent gas temperature for Type BH Class IIB vents?
A. 90°C (195°F)
B. 110°C (230°F)
C.
243°C (470°F)
D. 288°C (550°F)
10. What is the maximum vent gas temperature for Type B vents?
A. 90°C (195°F)
B. 110°C (230°F)
C.
243°C (470°F)
D. 288°C (550°F)
11. What is the maximum vent gas temperature for Type BH Class IIC vents?
A. 90°C (195°F)
B. 110°C (230°F)
C.
243°C (470°F)
D. 288°C (550°F)
12. What type of BH vent is CPVC?
A. Class I
B. Class II A
C.
Class II B
D. Class II C
© 2020 Appliance Technical Institute of Canada
4
UNI T 22
13. What type of BH vent is Polypropylene?
A. Class I
B. Class II A
C.
Class II B
D. Class II C
14. What type of BH vent is PVC?
A. Class I
B. Class II A
C.
Class II B
D. Class II C
15. Except for a BH vent, what is the minimum height a vent must terminate above a flat roof?
A. 450 mm
B. 600 mm
C.
900 mm
D. 1500 mm
16. What is the minimum height a chimney must terminate above a flat roof?
A. 450 mm
B. 600 mm
C.
900 mm
D. 1500 mm
17. For a positive pressure BH vent, what is the minimum termination height above a flat roof?
A. 450 mm
B. 600 mm
C.
900 mm
D. 1500 mm
18. What is the minimum horizontal clearance from an obstruction to a vent termination without
increasing the height?
A. 2 ft. (0.6 m)
B. 4 ft. (1.22 m)
C.
8 ft. (2.44 m)
D. 10 ft. (3.66 m)
© 2020 Appliance Technical Institute of Canada
5
UNI T 22
19. As per Table 8.6 what is the minimum Type C vent connector clearance for a boiler?
A. 25 mm
B. 75 mm
C.
150 mm
D. 225 mm
© 2020 Appliance Technical Institute of Canada
6
UNI T 22
Unit 22 – Chapter 03: Vent design and installation requirements for Category I appliances
1.
Which category of appliance can be vented using the Annex C Code tables?
A. Category I
B. Category II
C.
Category III
D. Category IV
2.
A Type B vent passing through an unused masonry chimney flue shall be considered an exterior
chimney.
A. True
B. False
3.
When reducing the size of a vent connector from that of the draft-hood, what is the minimum total
vent height required?
A. 5 ft
B. 10 ft
C.
15 ft
D. 20 ft
4.
When sizing the vent for a high altitude installation, which rating is used when determining
maximum capacity?
A. Sea level rating
B. High altitude rating
C.
Sea level rating plus 4%
D. High altitude rating plus 4%
5.
A single fan-assisted furnace may be vented into a tile lined masonry chimney.
A. True
B. False
6.
A fan-assisted furnace may be vented into a masonry chimney that is serving a draft-hood-equipped
appliance.
A. True
B. False
7.
The vent for a fan assisted appliance with a ” flue collar may be reduced to ” if determined by the
tables.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
7
UNI T 22
8.
A single vented fan-assisted appliance requires 3 elbows for the vent connector. How will the table
capacity need to be adjusted?
A. Reduced by 5%
B. Reduced by 10%
C.
Reduced by 15%
D. Reduced by 25%
9.
When the vent table permits more than one diameter of pipe that can be used for a connector or the
vent, which is preferred: the larger or the smaller?
A. Larger connector or vent
B. Smaller connector or vent
C.
Smaller connector and larger vent
D. Larger connector and smaller vent
10. If the vent connectors are connected to a horizontal common vent connector manifold, how must the
common vent capacity table be adjusted?
A. Increase 10%
B. Reduced by 10%
C.
Increase by 11%
D. Reduced by 11%
11. If the common vent is offset, how must the common vent capacity table be adjusted?
A. Increase 20%
B. Reduced by 20%
C.
Increase by 251%
D. Reduced by 25%
© 2020 Appliance Technical Institute of Canada
8
UNI T 22
12. Of the three configurations shown, which is the least effective in minimizing spillage?
(a)
(b)
(c)
A. Configuration (a)
B. Configuration (b)
C.
Configuration (c)
D. Configuration (b &c)
© 2020 Appliance Technical Institute of Canada
9
UNI T 22
Unit 22 – Chapter 04: Size venting systems for Category I appliances
1.
Size the individual vent for the following system specifications:
Height: 35 ft.
Lateral: 10 ft.
Vent connector: Single wall
Appliance: NAT
Input: 265 Mbtu/h
Structure: Tight
2.
A.
”
B.
”
C.
”
D.
”
Size the individual vent size for the following system specifications:
Height: 20 ft.
Lateral: 5 ft.
Vent connector: Single wall
Appliance: FAN
Input: 160 Mbtu/h
Structure: Tight
3.
A.
”
B.
”
C.
”
D.
”
Size the vent connector of appliance #1 for the following system specifications:
Height: 32 ft.
Rise #1: 3 ft.
Rise #2: 3 ft.
Vent connectors: Single wall
Appliances: FAN/NAT
Input Appliance #1: 40 Mbtu/h (NAT)
Input Appliance #2: 165 Mbtu/h (FAN)
Structure: Tight
A.
”
B.
”
C.
”
D.
”
© 2020 Appliance Technical Institute of Canada
10
UNI T 22
4.
Size the vent connector of appliance #2 for the following system specifications:
Height: 32 ft.
Rise #1: 3 ft.
Rise #2: 3 ft.
Vent connectors: Single wall
Appliances: FAN/NAT
Input Appliance #1: 40 Mbtu/h (NAT)
Input Appliance #2: 165 Mbtu/h (FAN)
Structure: Tight
5.
A.
”
B.
”
C.
”
D.
”
Size the common vent for the following system specifications:
Common vent has an offset using two 90° elbows
Height: 15 ft.
Rise #1: 1 ft.
Rise #2: 3 ft.
Vent connectors: B vent
Appliances: FAN/NAT
Input Appliance #1: 75 Mbtu/h (NAT)
Input Appliance #2: 250 Mbtu/h (FAN)
Structure: Tight
A.
”
B.
”
C.
”
D.
”
© 2020 Appliance Technical Institute of Canada
11
UNI T 22
6.
Size the vent connector for the following system specifications:
Individual appliance connected to a masonry chimney
Height: 10 ft.
Lateral: 5 ft.
Vent connectors: B vent
Appliances: NAT
Input: 200 Mbtu/h
Structure: Loose
7.
A.
”
B.
”
C.
”
D.
”
What is the minimum internal area of a masonry chimney serving an individual appliance with the
following system specifications:
Individual appliance connected to a masonry chimney
Height: 10 ft.
Lateral: 5 ft.
Vent connectors: B vent
Appliances: NAT
Input: 200 Mbtu/h
Structure: Loose
A. 38 in2
B. 50 in2
C.
198 in2
D. 269 in2
8.
What is the maximum internal area of a masonry chimney serving an individual appliance with the
following system specifications:
Individual appliance connected to a masonry chimney
Height: 10 ft.
Lateral: 5 ft.
Vent connectors: B vent
Appliances: NAT
Input: 200 Mbtu/h
Structure: Loose
A. 38 in2
B. 50 in2
C.
198 in2
D. 269 in2
© 2020 Appliance Technical Institute of Canada
12
UNI T 22
9.
What is the maximum length of an offset on a ” common vent
A. 4 ft.
B. 7.5 ft.
C.
9 ft.
D. 12 ft.
10. As per Clause 8.12.8, what is the maximum listed table capacity of a chimney serving an appliance
with an input of 120 Mbtu/h?
A. 113 Mbtu/h
B. 150 Mbtu/h
C.
187 Mbtu/h
D. 200 Mbtu/h
© 2020 Appliance Technical Institute of Canada
13
UNI T 22
Unit 22 – Chapter 05: Vent inspection
1.
What is the most serious and hazardous venting problem?
A. Corrosion
B. Condensation
C.
Flue gas spillage
D. Insufficient support
2.
What is the most common cause of flue gas spillage on Category I appliances?
A. Building depressurization
B. Improper vent configuration
C.
Incorrectly sized venting system
D. Blocked or restricted venting system
3.
Category I fan-assisted appliances are more prone to suffer condensation problems from oversized
venting systems?
A. True
B. False
4.
What is the purpose of a spill switch?
A. Sense a gas leak
B. *Sense a blocked vent
C.
Sense a water supply leak
D. Signal water pressure relief valve activation
5.
How can you remedy joint leakage problems with a Type B vent system installed on a Category IV
appliance?
A. Increase the vent size
B. Increase the vent height
C.
Tape the joints externally
D. Replace system with a proper Type BH vent
© 2020 Appliance Technical Institute of Canada
14
UNI T 22
Unit 22 – Chapter 06: Air requirements
1.
How are air supply requirements for a direct vent appliance determined?
A.
B.
C.
D.
2.
What is the minimum required free area of a square combustion air opening?
A.
B.
C.
D.
3.
Table 8.1
Table 8.2
Code clause 8.2.6
Manufacturer’s literature
3 in2
6 in2
9 in2
10 in2
The combustion air supply for a less than 400 MBtu/h installation must terminate within __________
above, and within ____________ horizontally from the burner level of the appliance having the largest
input.
A. 1’ , 2’
B. 2’ , ’
C.
’, ’
D. ’ , ’
4.
What is the smallest opening dimension in a fixed louvre, grille, or screen?
A.
B.
C.
D.
5.
1/ ”
1/ ”
1/2”
1”
Under what conditions can a gas-fired appliance be installed in a building and not have a separate
combustion air supply?
A. Tight building of sufficient volume
B. Loose building of less than 1000 ft2
C.
Loose building of sufficient volume
D. Tight building appliance in an enclosure
6.
When compared to the air supply opening, what is the minimum cross-sectional area of the
ventilation air opening for an appliance over 400 MBtu/h?
A. 5% or 5 in2
B. 10% or 10 in2
C.
20% or 20in2
D. 50% or 50 in2
© 2020 Appliance Technical Institute of Canada
15
UNI T 22
7.
A single family dwelling complies with Clause 8.2.1(a) or (b). It has a boiler rated at 200 MBtu/h and
a hot water storage tank rated at 110 MBtu/h. Both appliances are equipped with draft control
devices. The air supply is brought from outdoors through a duct. Determine the area of air supply
duct.
A. 22 in2
B. 25 in2
C.
40 in2
D. 47 in2
8.
A structure conforms to Clause 8.2.1(a) or (b). It contains a boiler rated at 65 MBtu/h and a domestic
hot water tank rated at 40 MBtu/h. Both appliances are designed for use with no draft control
devices and the air supply is brought from outdoors through a duct. Determine the area of air supply
duct.
A. 7 in2
B. 9 in2
C.
14 in2
D. 18 in2
9.
A single family dwelling conforms to Clause 8.2.1(a) or (b). It has a furnace rated at 80 kW and a hot
water tank rated at 30 kW. The furnace is equipped with a barometric draft control and the hot water
tank has a draft-hood. The air supply is from outdoors. Determine the area of air supply duct.
A. 12,000 mm2
B. 14,000 mm2
C.
30,000 mm2
D. 35,000 mm2
10.
A structure conforms to Clause 8.2.1(a) or (b). It has a mid-efficient furnace rated at 150 MBtu/h and
a hot water tank with an input of 40 MBtu/h. The furnace has no draft control device, but the hot
water tank is equipped with a draft-hood. The air supply is from outdoors. Determine the area of air
supply duct.
A. 4 in2
B. 14 in2
C.
29 in2
D. 18 in2
11. A structure does not comply with Clause 8.2.1(a) or (b). It is equipped with a boiler rated at 150
MBtu/h and a hot water tank rated at 60 MBtu/h. Both appliances are equipped with draft control
devices. The volume of the structure is 8000 cu ft. Determine the area of air supply duct.
A. 16 in2
B. 29 in2
C.
32 in2
D. None required
© 2020 Appliance Technical Institute of Canada
16
UNI T 22
12. A structure does not conform to Clause 8.2.1(a) or (b). It is equipped with a boiler rated at 225
MBtu/h and a hot water tank rated at 50 MBtu/h. Both appliances do not use a draft control device
and the volume of the structure is 10 000 cu ft. Determine the area of air supply duct.
A. 20in2
B. 32 in2
C.
40 in2
D. None required
13. A boiler room is located within an enclosure in a structure that does not comply with Clause 8.2.1(a)
or (b). The boiler is rated at 200 MBtu/h and a hot water tank is rated at 60 MBtu/h. Both units are
equipped with draft-hoods. The volume of the structure is 20 000 cu ft and Table 8.3 indicates that
the air supply may be taken from the structure. Calculate the area of openings required to be cut into
the enclosure.
A. 20in2
B. 260 in2 upper and lower
C.
260 in2 upper opening only
D. 260 in2 lower opening only
14. A mechanical room is equipped with gas appliances with a total input of 1800 MBtu/h. All appliances
are equipped with draft control devices. Determine the free area of air supply opening.
A. 18 in2
B. 60 in2
C.
201 in2
D. 260 in2
15. A structure is equipped with a boiler rated at 400 MBtu/h and a hot water tank rated at 80 MBtu/h.
Both pieces of equipment are equipped with draft control devices and the air supply is ducted from
outdoors. Determine the free area of ventilation opening
A. 7 in2
B. 10 in2
C.
12 in2
D. 68 in2
16. A structure is equipped with a boiler rated at 1000 kW and has a barometric draft control. Determine
the free area of air supply opening.
A. 70,000 mm2
B. 201,500 mm2
C.
310,000 mm2
D. None required
© 2020 Appliance Technical Institute of Canada
17
UNI T 22
17. A structure is equipped with appliances rated at 2000 MBtu/h. None of the appliances are equipped
with draft control devices. Determine the free area of air supply opening.
A. 10in2
B. 67 in2
C.
214 in2
D. 285 in2
18. A structure is equipped with appliances rated at 600 kW of input. The appliances do not have any
draft control devices and the air is supplied from outside. Determine the free area of air supply
opening
A. 42,000 mm2
B. 93,000 mm2
C.
139,500 mm2
D. 310,000 mm2
19. A structure has a mechanical room into which air must be ducted from outdoors. It contains the
following appliances:
•
One boiler rated at 1200 MBtu/h, equipped with a barometric damper.
•
Two duct heaters without draft controls rated at 600 MBtu/h each.
•
Two hot water tanks rated at 300 MBtu/h each. Both tanks are equipped with draft-hoods.
Determine the free area of air supply opening
A. 80 in2
B. 171 in2
C.
220 in2
D. 240 in2
20. Calculate the air requirements supplied from outdoors to a mechanical room equipped with the
following appliances:
•
One boiler with a draft control at 200 kW.
•
One boiler with no draft control rated at 100 kW.
•
Two duct heaters with no draft control rated at 50 kW each.
•
Two hot water tanks with draft-hoods at 100 kW each.
Determine the free area of ventilation opening
A. 4,200 mm2
B. 11,250 mm2
C.
12,250 mm2
D. 13,950 mm2
© 2020 Appliance Technical Institute of Canada
18
Answers
Unit 22 – Chapter 01: Venting systems
1. B
2. A
3. D
4. C
5. B
6. B
7. A
8. B
9. A
10. B
Unit 22 – Chapter 02: Vent installation and assembly
1. A
2. C
3. B
4. D
5. C
6. A
7. D
8. D
9. A
10. C
11. B
12. C
13. D
14. B
15. B
16. C
17. A
18. D
19. C
Unit 22 – Chapter 03: Vent design and installation requirements for Category I appliances
1. A
2. B
3. B
4. A
5. B
6. A
7. A
8. C
9. B
10. B
11. B
12. A
Unit 22 – Chapter 04: Size venting systems for Category I appliances
1. D
2. B
3. A
4. B
5. D
6. C
7. B
8. D
9. C
10. B
Unit 22 – Chapter 05: Vent inspection
1. C
2. A
3. A
4. B
5. D
Unit 22 – Chapter 06: Air requirements
1. D
2. C
3. A
4. B
5. C
6. B
7. D
8. B
9. D
10. B
11. C
12. D
13. B
14. C
15. B
16. B
17. B
18. A
19. D
20. C
© 2020 Appliance Technical Institute of Canada
2
G2 Gas Technician Module 22
1.
A 7 " diameter vent connector is
serving an appliance with a draft
hood. what is the minimum gauge of
material?
No. 26 GSG Clause
8.18.3
2.
An appliance requiring zero over
fire draft shall be installed with a ?
Draft hood
3.
Can an oil burning appliance be
common vented with a gas burning
appliance in the same chimney
flue?
Yes clause 8.10.2
If a vent terminates to a paved
sidewalk it shall not be less than?
7 feet above
5.
If a water heater has an input of
50000 btuh or less and is the only
appliance in the structure does it
require outdoor combustion air to
be brought in?
No clause 8.2.3
6.
If the common vertical vent is
offset using two 90 degree elbows
what must be done to the capacity?
must be reduced by
20%
7.
A power venter that is used as an
add-on to a water heater can only
be used if the input does not
exceed?
50000 Btuh clause
8.29.2
8.
A single acting type draft regulator
is ususally used on?
Incinerator
9.
A square or rectangular shape duct
shall only be used whn the required
free air supply opening is?
9 square inches or
greater clause 8.3.2
10.
What are B vents?
Are double walled
vents that can run
through a ceiling to
the outside
4.
11.
What are type C vent connectors?
What are some limitations?
1. They are single wall
vent connectors made
of galvanized steel.
2. They are not
allowed to go
through floors,
ceilings or concealed
areas of the building
structure.
12.
What are Type
L vents? Where
are they used?
What is max
flue temp?
1. They are double walled insulated vents
with interior wall constructed of stainless
steel
2. They are used when heat/corrosion
could be a problem
3. Must not exceed 550 F
13.
What does
direct venting
do?
Supplies combustion air directly from the
outside and expels flue gases directly to
the outside.
14.
What does flue
loss determine?
If the appliance is a condensing system.
15.
What do special
venting
systems do?
They are used with high efficient or
condensing furnaces. They condense the
flue gases to release more heat back into
the building. Latent heat of 1 lb of water
vapor converting to liquid will release 970
btu back into the structure.
16.
What is a BH
Vent? When is
it used? What
kind of flue
temps?
1. They are single walled flexible stainless
steel pipe or S636 schedule 40 pvc
plastic pipe.
2. Used in high efficient condensing
furnaces
3. Use in low flue temperatures and
positive vent pressures
17.
What is an
example of a
positive vent
pressure
system? Non positive
system?
Positive - Hi eff. furnace
Non positive - natural draft
18.
What is a type
A vent?
They are chimneys made of masonry or
steel
19.
What is the
maximum flue
gases should be
for a natural
draft system?
Why?
450 F is the max this is because safety
concerns of having high heat in a
combustible building and the hotter the
gasses the more inefficient the system is.
20.
What is the
maximum
lateral length
for a 6 " single
wall vent
connector?
Double wall?
10 ft - single wall
20 ft - double wall
Table C.9 (double distance for double
wall)
21.
What is the minimum flue
gas temperature should be?
Why?
Greater then 127 F, this is
when the flue gases will
condense causing corrosion
due to its highly acidic nature
22.
What is the minimum wall
dimension a square or
rectangular duct can have?
3 " clause 8.3.2
What must be done to an
exterior chimney?
It must be insulated
24.
What must be done when
vent connectors are
combined prior to entering
the common vent?
Capacity must be reduced by
10%
25.
What pressure does
atmospheric pressure exert
on the earth at sea level?
14.74 psia
26.
What two things mean you
must bring in combustion
air.
1. Total BTU of appliance if
greater than 400000 you
must bring in combustion air.
2. If house is tight
construction you also must
bring in air.
27.
When bringing in
ventilation air what is the
minimum cross sectional
area allowed?
10 " clause 8.4.1
28.
When can fan assisted
appliances be connected to
a clay lined masonry
chimney?
When it is common vented
with another appliance that is
equipped with a draft control
device
29.
When sizing a vent
connector with 3 or greater
90 Degree elbows what
must be done?
Reduce the capacity by 10%
per elbow. 2 elbows are
already assumed in the charts
calculation. clause C.2.4
30.
When using a chimney liner
what tables must be used?
What must be done to the
Btuh capacities?
Use the B-vent tables and the
capacities must be reduced
by 20%
31.
When using the vent sizing
tables what must be done
with the fan assisted
appliances btuh?
They must fall between the
min and max on the chart
23.
32.
When you have a vent
connector sharing a common
vent between a draft controlled
appliance and a non draft
controlled appliance what must
be done?
The draft controlled
appliance must enter the
vent above the fan
assisted one.
33.
Where can't a single wall vent
connector pass?
Floor or ceiling
34.
Where must the air supply duct
from outside be located?
within 1 ft above, and
within 2 ft horizontally
from the burner level of
the appliance having the
largest output. clause
8.3.1.d
35.
Where shall a baffle or neutral
pressure point adjuster be
located?
Upstream of the draft
regulator
Module 23
Forced Air Ad-On
Devices
© 2020 Appliance Technical Institute of Canada
UNI T 23
Unit 23 – Chapter 01: Air filters and cleaners
1.
If the filter is lightly soiled, vacuuming will be sufficient to remove the particles. What side of the
filter should be vacuumed first?
A. Upstream side
B. Either side first
C.
Downstream side
D. Varies from furnace to furnace
2.
Which type of air cleaner is usually the least expensive?
A. Media
B. Electronic
C.
Electrostatic
D. UV purifier
3.
When installing an activated carbon filter with an electronic air cleaner, were should the activated
carbon filter be located.
A. Upstream of the EAC
B. In the bypass air duct
C.
Downstream of the EAC
D. In the ventilation air intake
4.
What type of filter is recommended to use for reducing smoke odours?
A. UV air purifier
B. Electrostatic filter
C.
Electronic air cleaner
D. Activated carbon filter
5.
If there are arrows on a filter frame, which way must they face?
A. Up
B. Down
C.
With the flow
D. Against the flow
6.
Because electrostatic filters are a form of slab filter, they are installed in the same position and way
as slab filters.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
1
UNI T 23
7.
Before opening the blower door on a forced-air furnace always disconnect the power supply.
A. True
B. False
8.
How frequently should furnace filters be inspected in the heating season?
A. Daily
B. Weekly
C.
Monthly
D. Seasonally
9.
How frequently should filters be replaced?
A. Monthly
B. Annually
C.
At least twice a year
D. At least every two years
10. On an existing system without any modifications, what is the most common cause of inadequate
heating or cooling performance?
A. Underfired
B. Dirty filters
C.
Venting problem
D. Malfunctioning thermostat
11. What damage can a dirty filter do in a system that includes add-on air conditioning?
A. Cause floodback
B. Compressor damage
C.
Decrease cooling performance
D. Any of the choices could occur
12. The pre-filter of an EAC serves the same purpose as the filter in the furnace blower compartment,
therefore that filter should be removed when an EAC is installed.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
2
UNI T 23
13. What can happen if ionizer wires are broken?
A. Sail switch remains open
B. Air flow will be restricted
C.
Visible arcing and sparking
D. Voltage indicator light will be light
14. After washing the cells of an EAC leave it turned off for two or three hours until the cells and prefilter are completely dry to avoid problems.
A. True
B. False
15. If cells are washed in a dishwasher, why should the drying cycle not be run?
A. Cells will be melted
B. Cell coating will be damaged
C.
Heat will damage the cells magnetic properties
D. Any remaining contaminants will be baked onto cells
16. To ensure customers have the best air quality it is recommended to always install a filter with the
highest MERV rating
A. True
B. False
17. A HEPA filter is best installed as a stand-alone system or a partial bypass system.
A. True
B. False
18. What type of UV lights are most commonly used for germicidal air treatment?
A. UVA
B. UVB
C.
UVC
D. VUV
19. When installing a UV air treatment bypass system or a HEPA bypass system you must remove the
furnace inline blower compartment filter.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
3
UNI T 23
Unit 23 – Chapter 02: Humidifiers
1.
What is the approximately ideal level of relative humidity for optimum comfort in a residence?
A. 10%
B. 20%
C.
40%
D. 60%
2.
What type of humidifier has a water reservoir that the wetted element is drawn through?
A. Drum humidifier
B. Steam humidifier
C.
Atomizing humidifier
D. Evaporator Pad humidifier
3.
Atomizing humidifiers introduce droplets of water into the air.
A. True
B. False
4.
Why should atomizing humidifiers operate only when the furnace blower is operating?
A. Water could collect in the ducts
B. Humidity levels in the building can get to high
C.
The outdoor air temperature cannot be sensed
D. The furnace heat exchanger will be cooled to low
5.
How does the steam supply hose or pipe have to be installed on a self-contained steam humidifier?
A. Installed perfectly level
B. Looped to create as running trap
C.
Pitched down from dispersion tube to humidifier
D. Pitched down from humidifier to dispersion tube
6.
The humidistat is normally mounted on the supply air duct.
A. True
B. False
7.
Why do digital humidistats, on automatic mode, adjust the building humidity based on outside air
temperature?
A. Colder days required lower indoor relative humidity for optimal comfort
B. Warmer days required lower indoor relative humidity for optimal comfort
C.
Colder days required lower indoor relative humidity to avoid interior condensation
D. Warmer days required lower indoor relative humidity to avoid interior condensation
© 2020 Appliance Technical Institute of Canada
4
UNI T 23
8.
If excessive dust in a building is coming from the humidifier, how can it be identified?
A. It will be grey in colour
B. It will be black in colour
C.
It will be white in colour
D. It will be brown in colour
9.
What device controls the operation of a humidifier?
A. Fan switch
B. Humidistat
C.
Thermostat
D. Solenoid valve
10. If a humidifier is used in a system with an electronic air cleaner, where should the humidifier be
mounted?
A. Upstream of the EAC
B. Downstream of the EAC
C.
They cannot be combined
D. Any location is satisfactory
11. If not cleaned the water holding reservoir may breed bacteria that could be dispersed throughout the
house.
A. True
B. False
© 2020 Appliance Technical Institute of Canada
5
UNI T 23
Unit 23 – Chapter 03: Cooling coils
1.
Ref ige an ci c la e be
een he A c il and he c nden e c il Wha
cc
in the A coil?
A. Liquid refrigerant absorbs heat and changes to the vapour state
B. Vapourous refrigerant absorbs heat and changes to the liquid
C.
Heat is removed causing the vaporous refrigerant to return to a liquid state
D. Heat is removed, causing the liquid refrigerant to change to the vapour state
2.
Ref ige an ci c la e be
condenser coil?
een he A c il and he c nden e c il Wha
cc
ide in he
A. Liquid refrigerant absorbs heat and changes to the vapour state
B. Vaporous refrigerant absorbs heat and changes to the liquid
C.
Heat is removed causing the vaporous refrigerant to return to a liquid state
D. Heat is removed, causing the liquid refrigerant to change to the vapour state
3.
How would a dirty cooling coil affect the temperature change of the forced air furnace during the
cooling season?
A. The temperature drop would increase
B. The temperature drop would decrease
C.
The temperature rise would increase
D. The temperature rise would decrease
4.
What should be done first if you have a static pressure across the coil that is beyond the
man fac e
gge ed limi
A. Clean the unit
B. Clock the appliance
C.
Adjust the blower speed
D. Measure the temperature change
5.
A dirty cooling coil can restrict the air flow. What would be the effect on the temperature change of
the forced air furnace during the heating season?
A. The temperature drop would increase
B. The temperature drop would decrease
C.
The temperature rise would increase
D. The temperature rise would decrease
© 2020 Appliance Technical Institute of Canada
6
Answers
Unit 23 – Chapter 01: Air filters and cleaners
1. A
2. A
3. C
4. C
5. C
6. A
7. A
8. C
9. C
10. B
Unit 23 – Chapter 02: Humidifiers
1. C
2. A
3. A
4. A
5. C
6. B
7. C
8. C
9. B
10. B
11. A
Unit 23 – Chapter 03: Cooling coils
1. A
2. C
3. B
4. A
5. C
11. D
12. A
13. C
14. A
15. D
16. B
17. A
18. C
19. B
G2 Gas Technician Module 23
1.
Describe the basic function of
an electronic air cleaner.
Particles are energized by
ionizing wire and given a
positive or negative charge
that collects particles
16.
Name three factors that may be
present in a home that would
suggest cleaning must be more
frequent?
Pets, smoking, and
woodworking
2.
Do electronic air cleaners
remove smoke odours from
the conditioned air?
No
17.
Name three problems that can
result from operating a forced-air
furnace without a filter?
Dust and lint
buildup, Inefficiency
and Fire
3.
How can clean filters save the
customer money?
Preventing equipment
damage
18.
Media, electrostatic,
and electronic
4.
How can smoke odours be
reduced?
Activated Carbon Filter/
Coal Filter
Name three types of air cleaners
that can be used with a forced-air
furnace?
19.
How can the external surfaces
of a coil be cleaned?
Brushed, Vacuumed, and
Low pressure water
Name two advantages of an
electronic air cleaner?
Highly Efficiency and
Collects Particles
20.
6.
How frequently should filters
be replaced?
Twice a Year
Name two common problems that
can result from water overflow from
a humidifier?
Mildew and
Corrosion
7.
How frequently should
furnace filter be inspected in
the heating season?
Every Month
21.
What additional kind of cleaning
must be done if untreated water is
used as the cooling medium?
Probe the drain hole
with screwdriver
8.
If a humidifier is used in a
system with an electronic air
cleaner, where should the
humidifier be mounted?
Downstream of the EAC
22.
What are the four components of an
electronic air cleaner?
Pre Filter, Charging
Section, Collecting
Section, and Power
Pack
9.
If cells are washed in a
dishwasher, why should the
drying cycle not be run?
It will bake on the
contaminants and impair air
cleaners efficiency
23.
What are two ways in which a
mechanical filter could restrict air
flow?
Dirty Air Filter and
Incorrect Air Filter
10.
If excessive dust in a building
is coming from the humidifier,
how can it be identified?
The dust will be white
24.
What can happen if ionizer wires are
broken on an electronic air filter?
Arcing and Sparking
25.
Electrical Shock
If the power pack is not
working, what should be
done?
Replace it
What can happen if the electronic
air filter is turned on when cells are
wet?
26.
If there are arrows on a filter
frame, which way must they
face?
Same way as the systems
air flow
What damage can a dirty filter do in
a system that includes add-on air
conditioning?
Inadequate Air Flow
and floodback
27.
Humidistat
If there are no viewing ports
allowing the technician to
view the coil, what must be
done?
Cut an inspection port
What device controls the operation
of a humidifier?
28.
What devices are used to measure
pressure drop across the coil?
Manometer
29.
List four problems that might
develop in a central furnace if
the cooling coil is not kept
clean?
Clogged or dirty fins, oil
leak and clogged drip tray
What does an oil leak from the coil
indicate?
A leak that must be
repaired
30.
What is the approximate level of
relative humidity for optimum
comfort in a residence?
40%
List three methods for
cleaning the cells of an
electronic air cleaner?
Power wash, automatic
dishwasher, and detergent
5.
11.
12.
13.
14.
15.
31.
What is the major difference between atomizing humidifiers
and other types of humidifiers?
It introduces small droplets of water directly into the duct air
stream or the conditioned space
32.
What is the most common cause of inadequate heating or
cooling performance?
Dirty Air Filter
33.
What must the gas technician do before installing any air
cleaner?
Comply with Manufacturers Instructions
34.
What three problems may caused by relative humidity that is
too low?
Temperature feels colder than it's actual temperature, static
increases, frequent virus, and sickness
35.
Where should the test holes for measuring static pressure be
drilled?
The cooling coil cabinet
36.
Which type of air cleaner is usually the least expensive?
Media/Mechanical
37.
Which type of air cleaner is usually the most expensive?
Electronic (EAC)
38.
Why are air cleaners installed ahead of heating or cooling
coils and air conditioners?
To protect the equipment from dust and increase efficiency
39.
Why can disposable filters not be re-used?
Removal of mineral oils will cause the filter to not operate
40.
Why must be done before opening the blower door on a
forced-air furnace?
Disconnect Power
41.
Why should atomizing humidifiers operate only when the
furnace blower is operating?
Moisture can accumulate causing corrosion and mildew
42.
Why should static pressure across the coil be measured?
If the pressure drop is to great the coils need to be cleaned
43.
Why would a cooling coil be added to a forced air furnace?
Adapts it for the use as a central air conditioner
Module 24
Air Handling
© 2020 Appliance Technical Institute of Canada
UNI T 24
Unit 24 – Chapter 01: Heat loss/Heat gain
1.
Which type of ventilation system can lead to problems with moisture laden air being driven onto the
wall cavities?
A. Natural ventilation
B. Balanced ventilation
C.
Supply fan ventilation
D. Exhaust fan ventilation
2.
Which type of ventilation system can cause problems with the venting action of fuel-fired appliances,
creating combustion product spillage or back-drafting?
A. Natural ventilation
B. Balanced ventilation
C.
Supply fan ventilation
D. Exhaust fan ventilation
3.
What is enthalpy?
A. Enthalpy is the dew point of a sample of air
B. Enthalpy is the total heat contained in a substance
C.
Enthalpy is the latent heat contained in a substance
D. Enthalpy is the sensible heat contained in a substance
4.
What is dewpoint?
A. The temperature required to change the state of a substance
B. The temperature based on a 10year average for a specific location
C.
The temperature below which moisture in the air begins to condense
D. The temperature above which moisture in the air begins to condense
5.
What is the term that describes the percentage of moisture in the air compared to the amount it
would hold if the air were saturated at the same temperature?
A. Dew point
B. Humidity ratio
C.
Relative humidity
D. Wet bulb temperature
6.
What is the term that indicates the actual amount of moisture found in the air?
A. Dew point
B. Humidity ratio
C.
Relative humidity
D. Wet bulb temperature
© 2020 Appliance Technical Institute of Canada
1
UNI T 24
7.
When the temperature on two sides of a material is different, heat flows from the cooler side to the
warmer side.
A. True
B. False
8.
What is the specific heat of air at standard conditions?
A. 0.018 Btu/lb
B. 0.2417 Btu/lb
C.
1.01 Btu/lb
D. 4.186 Btu/lb
9.
What is the danger of having too little ventilation in a dwelling?
A. Increased costs
B. Cool and Drafty
C.
Positive building pressures
D. A buildup of pollutants within the dwelling
© 2020 Appliance Technical Institute of Canada
2
UNI T 24
Unit 24 – Chapter 02: Air handling units
1.
What is the proper position of a gas fired duct furnace?
A. Upstream of air conditioning coil and air handling fan
B. Downstream of air conditioning coil and air handling fan
C.
Upstream of air conditioning coil and downstream of air handling fan
D. Downstream of air conditioning coil and upstream of air handling fan
2.
If multiple separately controlled and sequenced duct furnaces are installed in series within the same
duct, the upstream duct furnaces must operate before the downstream duct furnaces.
A. True
B. False
3.
A radial duct system can be used to increase headroom in a basement.
A. True
B. False
4.
On individual return air systems, what is usually done to ensure less resistance to air flow in the
return system?
A. Undercut doors
B. Slightly larger return air ducts
C.
Slightly smaller return air ducts
D. Include return air grilles in rooms without supply air
5.
Paint can make flexible duct connectors rigid and prevent them from absorbing vibration.
A. True
B. False
6.
What would indicate internal blockages may be present with a duct furnace? cycling on and off due to
the operation of the high temperature limit control or incorrect temperature rise across the heat
exchanger.
A. Increased CFM
B. Decreased temperature rise
C.
Increase motor current draw
D. Cycling on and off on high limit
7.
If the blower in a forced-air distribution system moves 2100 cfm of air through a 24 inch x 18 inch
duct?
A. 58 ft/min
B. 420 ft/min
C.
700 ft/min
D. 1000 ft/min
© 2020 Appliance Technical Institute of Canada
3
UNI T 24
8.
Select the statement that best defines velocity pressure.
A. Decrease in air pressure caused by friction
B. Pressure that is created by the air movement
C.
Pressure against which the blower has to work
D. Air pressure in the duct at right angles to the direction of air flow
9.
Where is the lowest air pressure in the ductwork of a forced air heating system?
A. On the supply side after the cooling coil
B. On the return side upstream of the filter
C.
On the return side between the furnace and the filter
D. On the supply side between the furnace and the cooling coil
10. If the flanges are closed on an adjustable motor pulley, what happens to the belt and pulley?
A. Belt is raised and pulley diameter gets larger
B. Belt is raised and pulley diameter gets smaller
C.
Belt is lowered and pulley diameter gets larger
D. Belt is lowered and pulley diameter gets smaller
11. If the motor pulley is increased to twice the original size, what would the blower speed be (in
relation to the original blower speed)?
A. No change in blower speed
B. ½ the original blower speed
C.
Twice the original blower speed
D. Four times the original blower speed
12. If a larger diameter blower pulley is installed, what will happen to air flow and to temperature rise
across the heat exchanger?
A. Air flow would increase and temperature rise would decrease
B. Air flow would decrease and temperature rise would increase
C.
Air flow would increase and temperature rise would increase
D. Air flow would decrease and temperature rise would decrease
13. If the fan compartment door on a forced air furnace is left off, what is the effect the blower motor?
A. Less work done by motor so current decreases
B. Less work done by motor so current increases
C.
More work done by motor so current increases
D. More work done by motor so current decreases
© 2020 Appliance Technical Institute of Canada
4
UNI T 24
14. A PSC motor with multiple windings gets lower efficiency at lower speeds
A. True
B. False
15. An ECM maintains an efficiency range between 60% and 80%for all speeds
A. True
B. False
16. Calculate the air velocity for a velocity pressure reading of 0.04 inches of w.c.
A. 566 ft/min
B. 801 ft/min
C.
1132 ft/min
D. 1602 ft/min
© 2020 Appliance Technical Institute of Canada
5
Answers
Unit 24 – Chapter 01: Heat loss/Heat gain
1. C
2. D
3. B
4. C
5. C
6. B
7. B
8. B
9. D
Unit 24 – Chapter 02: Air handling units
1. C
2. A
3. B
4. B
5. A
6. D
7. C
8. B
9. C
10. A
11. C
12. B
13. B
14. A
15. A
16. B
G2 Gas Technician Module 24
1.
An adjustable sheave pully is
most commonly used on a
blower shaft. True or False.
False
2.
Blocked air filter effect on
current draw?
Decrease
3.
Blocked cooling coil effect
on current draw?
Decrease
4.
Can Gas Technicians conduct
heat loss calculations True or
False?
True if trained
5.
Decrease in cfm effect on
current draw?
Decrease
6.
Define relative humidity?
the amount of water vapor
present in air expressed as a
percentage of the amount
needed for saturation at the
same temperature.
7.
Identify three easy to fix
problems that can restrict air
flow through ducts?
Dampers closed, Registers
closed, and leaks in the
supply duct
8.
If a belt on a blower is to
tight, the blower motor
current will decrease True or
False?
False
If a larger diameter blower
pulley is installed, what will
happen to air flow and to
temperature rise across the
heat exchanger?
Air flow decreases and temp
rise increase
If the fan compartment door
on a forced air furnace is left
off, the blower motor current
will increase. True or False?
True
11.
If the motor pulley is twice
the diameter of the blower
pulley, what would the
blower speed be?
Greater
12.
Increase in blower speed
effect on current draw?
Increase
13.
Increase in motor horse
power rating effect on
current draw?
Increase
14.
Increase in static pressure
effect on current draw?
Decrease
9.
10.
15.
List at least two
problems that can be
caused by an improperly
sized duct system.
Noisy if to fast and improper
change in temp across heat
exchanger or cooling coil if to
slow
16.
List four properties of air
that affect building
comfort.
Temperature, Humidity, Enthalpy
and Volume
17.
List three types of
clearance distance that
must be maintained
when installing a duct
furance.
Clearance required from
combustible material, clearance
to fresh air intake and
dampers/restriction prohibitation
18.
List two sources of
regulations and
standards of practice
that influence decisions
concerning air flow in
residential construction.
F280 and F326
19.
Name the terms used to
describe a ventilation
distribution system.
Dedicated, Integrated and
Through the Wall
20.
Name three methods of
heat transfer.
Conduction, Convection and
Radiant
21.
Open blower cabinet
door effect on current
draw?
Increase
22.
What damage will be
evident on the belts in a
belt-driven blower if the
pulleys are not aligned
properly?
the sides of the belt will wear
more quickly than usual
23.
What is enthalpy?
All of sensible heat, latent heat
contained in a substance when
heat is being transfer
24.
What is the danger of
having to little
ventilation in a dwelling
unit?
A build-up pollutants in the air
25.
What three factors must
be included when air
flow in a building is
calculated.
Velocity of air/function of the
strength of the blower and size
of duct, Volume of Air moving
through the ducts and the effect
of friction from ducts and fittings
on the air flow
26.
What two purposes do
duct liners serve?
Reduce sound and minimize heat
transfer
27.
What two things must be known before the correct size
blower can be chosen for a building?
Static pressure drop for system and the required air flow rate for
the building
28.
Where is the lowest pressure in the ductwork of a forced air
heating system?
Return Pleanum
29.
Why is air movement an important consideration for building
comfort?
Air movement decrease or increase the rate of heating gain or
loss from building and human bodies
30.
Why should flexible duct connectors not be painted?
it could make the flex connector rigid and prevent it from
absorbing vibration
Gas Technician 2
Practical Workbook
© 2020 Appliance Technical Institute of Canada
Gas Technician 2
Practical Project Handbook
Instructions
All projects in this handbook must be completed prior to the end of your program and before
writing your TSSA Gas Technician 2 examination.
Student Name: _____________________________________
Start Date: ________________________________________
Date Handbook Completed: __________________________
© 2020 Appliance Technical Institute of Canada
1
Gas Technician 2 – Practical Assignments
Table of Contents
Assignments to be completed by the end of the course
1. Natural Draft Furnace Report
Page 3
2. Mid-Efficiency Furnace Report
Page 4
3. High-Efficiency Furnace Report
Page 5
4. Boiler Report
Page 6
5. Pool Heater Report
Page 7
6. Natural Draft Water Heater Report
Page 8
7. Power Vented Water Heater Report
Page 9
8. Clothes Dryer Report
Page 10
9. Cook Stove Report
Page 11
10. Fireplace Report
Page 12
11. Low Intensity Radiant Heater Report
Page 13
12. High Intensity Radiant Heater Report
Page 14
13. Tankless Water Heater Report (combo unit)
Page 15
14. Thermocouple Circuit Test
Page 16
15. Flame Signal Proving Test
Page 17
16. Air Temperature Rise and Air Flow Test
Page 18
17. Replacement of a Gas Fired Water Heater
Page 19
18. Replacement of a Gas Fired Furnace
Page 20
19. Electrical Wiring of a Gas Fired Furnace
Page 21
20. Electrical Circuit Readings
Page 22
© 2020 Appliance Technical Institute of Canada
2
Practical Assignment 1
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
NATURAL DRAFT FURNACE
Fire up furnace and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
High limit setting
Circulating air blower motor rated amperage
Circulating air blower motor amperage draw
Circulating air blower motor horsepower
Required air temperature rise
As per rating plate:
Blower motor on / off settings
Type of ignition system
As per control settings:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
As per control setting:
As per rating plate:
Actual:
As per rating plate:
As per rating plate:
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
3
Practical Assignment 2
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
MID - EFFICIENCY FURNACE
Fire up furnace and enter the following information
Appliance manufacturer s name
As per rating plate:
Type of appliance
Model Number
As per rating plate:
Serial Number
As per rating plate:
B.T.U.H input rate
As per rating plate:
Fuel Type (natural gas or propane gas)
As per rating plate:
Building line pressure maximum (“ w.c.)
As per rating plate:
Appliance manifold pressure (“ w.c.)
As per rating plate:
Clocking the meter (c.f.h.)
B.T.U.H input rate (actual):
High limit setting
As per control setting:
Circulating air blower motor rated amperage
As per rating plate:
Circulating air blower motor amperage draw
Actual:
Circulating air blower motor horsepower
As per rating plate:
Draft induced blower motor rated amperage
Draft induced blower motor amperage draw
Draft induced blower motor rated horsepower
Blower motor on / off settings
As per control settings:
Type of ignition system
Which speed is blower motor set at?
Required air temperature rise
As per rating plate:
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
4
Practical Assignment 3
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
HIGH - EFFICIENCY FURNACE
Fire up furnace and enter the following information
Appliance manufacturer s name
As per rating plate:
Type of appliance
Model Number
As per rating plate:
Serial Number
As per rating plate:
B.T.U.H input rate
As per rating plate:
Fuel Type (natural gas or propane gas)
As per rating plate:
Building line pressure maximum (“ w.c.)
As per rating plate:
Appliance manifold pressure (“ w.c.)
As per rating plate:
Clocking the meter (c.f.h.)
B.T.U.H input rate (actual):
High limit setting
As per control setting:
Circulating air blower motor rated amperage
As per rating plate:
Circulating air blower motor amperage draw
Actual:
Circulating air blower motor horsepower
As per rating plate:
Draft induced blower motor rated amperage
Draft induced blower motor amperage draw
Draft induced blower motor rated horsepower
Blower motor on / off settings
As per control settings:
Type of ignition system
Which speed is blower motor set at?
Required air temperature rise
As per rating plate:
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
5
Practical Assignment 4
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
HYDRONIC BOILER
Fire up boiler and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
High limit setting
Pump motor rated amperage
Pump motor amperage draw
Pump motor Horsepower
Pump motor on / off settings
Pump motor R.P.M
Type of ignition system
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
As per control setting:
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
6
Practical Assignment 5
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
POOL HEATER
Fire up pool heater and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
High limit setting
Type of ignition
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
As per control setting:
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
7
Practical Assignment 6
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
NATURAL DRAFT STORAGE WATER HEATER
Fire up water heater and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
Water temperature with control on low
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
8
Practical Assignment 7
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
POWER VENTED STORAGE WATER HEATER
Fire up furnace and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
Water temperature with control on low
Power vent blower motor rated amperage
Power vent blower motor amperage draw
Power vent blower motor R.P.M.
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
9
Practical Assignment 8
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
RESIDENTIAL CLOTHES DRYER
Fire up dryer and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
10
Practical Assignment 9
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
RESIDENTIAL STOVE (RANGE)
Fire up stove and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
11
Practical Assignment 10
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
FIREPLACE
Fire up fireplace and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
12
Practical Assignment 11
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
LOW INTENSITY RADIANT HEATER
Fire up radiant heater and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
13
Practical Assignment 12
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
HIGH INTENSITY RADIANT HEATER
Fire up furnace and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
14
Practical Assignment 13
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
TANKLESS WATER HEATER (combination unit)
Fire up furnace and enter the following information
Appliance manufacturer s name
Type of appliance
Model Number
Serial Number
B.T.U.H input rate
Fuel Type (natural gas or propane gas)
Building line pressure maximum (“ w.c.)
Appliance manifold pressure (“ w.c.)
Clocking the meter (c.f.h.)
Type of ignition
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
As per rating plate:
B.T.U.H input rate (actual):
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
15
Practical Assignment 14
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
OPEN / CLOSED AND DROP OUT THERMOCOUPLE CIRCUIT TEST
The pilot flame should be a steady blue colour
Fa e h de e
he he
c
e i 3/8
1/2"
Open circuit test:
1) Remove thermocouple end from gas valve
2) Connect the meter leads to tube and end of
contact point
3) Record millivolt meter reading:______mV
NOTE: Pilot plunger on gas valve must be
held down the entire time of test
Closed circuit test:
Drop out test:
1) Remove thermocouple from gas valve
2) Insert adaptor and re-insert thermocouple
3) Connect meter leads to thermocouple tube
and adaptor
4) Light pilot light
5) Record millivolt meter reading: ______mV
1) Using the closed circuit test procedure, turn
off the gas valve and record the reading when
the pilotstat coil de-energizes (you will hear a
click)
2) Record millivolt meter reading: ______mV
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
16
Practical Assignment 15
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
PROVING FLAME SIGNAL
Choose a gas appliance that utilizes a flame sensing electrode
Ensure that the power is turned off to the furnace before starting this project
1) Locate flame sensor near burner array
2) Remove wire from the flame sensing electrode
3) Attach one probe from your multi meter to the wire from the flame sensing electrode
4) Attach the other probe from your multimeter to the flame sensing electrode
5) You have now attached your multimeter in series with the flame sensing electrode and it s
connecting wire
6) Fire up the furnace and record the reading here: ______________ micro-amps
7) Shut off the power to the furnace and remove your multimeter probes
8) Re-attach the wire to the flame sensing probe
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
17
Practical Assignment 16
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
AIR TEMPERATURE RISE AND AIR FLOW TEST
1) Determining the air temperature rise of a gas fired forced air furnace
2) Determine the air flow in cubic feet per minute of the same furnace
3) Ensure all components are in working condition
1) Start the heating unit and allow it to operate for about 5 minutes
2) Meas re manifold press re and record
(adjust if required)
c
3) Determine the temperature rise of the circulating air through the unit and record: _____ OF
NOTE: Discharge air temperature (minus) Entering air temperature = Air temperature rise
4) Determine the blower C.F.M. And record: _________________ c.f.m.
5) Use the following formula:
(1.08 x air temperature rise difference) divided by B.T.U.H. output = C.F.M.
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
18
Practical Assignment 17
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
REMOVAL AND INSTALLATION OF A NATURAL DRAFT WATER HEATER
1) Shut off water supply and gas supply to water heater
2) Attach drain hose to drain cock of water heater and drain completely of water
3) Remove venting from water heater
4) Remove gas piping from water heater up to piping tee
5) Clean and cut cold copper a er lines
from op of a er hea er
6) Remove water heater from location and install new water heater
7) When new water heater is in its proper position, attach gas piping, water piping and
venting
8) Check all piping for leaks (water and gas)
9) Fire up water heater and conduct all necessary procedures to ensure water heater is
functioning properly
10) List all necessary procedures in the activity report below when installation is complete
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
19
Practical Assignment 18
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
REMOVAL AND ISTALLATION OF GAS FIRED FURNACE
1) Shut off water supply and gas supply to furnace
2) Disconnect electrical supply wire and thermostat wire from furnace
3) Remove venting from furnace
4) Remove gas piping from furnace up to manual shut off valve
5) Remove existing ductwork from furnace and draw the required plenum adaptors on back
of this sheet (if required)
6) Remove furnace from its location and position new furnace correctly
7) Attach new plenum adaptors, gas piping, venting, electrical supply wiring and thermostat
wiring
8) Check all gas piping for leaks
9) Fire up furnace and conduct all necessary procedures to ensure furnace is functioning
properly
10) List all necessary procedures in the activity report below when installation is complete
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
20
Practical Assignment 19
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
ELECTRICAL WIRING OF A GAS FIRED FURNACE
Furnace switch – 110V
Door switch – 110V
Thermostat – 24V
Flam roll out switch – 24V
Multi-speed circulating blower motor – 110V
High limit switch – 110V
Electronic air cleaner – 110V
Humidifier motor – 24V
Draft induced blower motor – 110V
Pressure Switch – 24V
Blower control – 110V
Humidistat – 24V
Step down transformer – 110V / 24V
Gas valve – 24V
R1 Control relay
R2 Control relay
Disconnects electrical power to furnace
If blower door is removed, unit will shut off
Energizes gas valve
De-energizes gas valve
High speed on temp rise
De-energizes transformer
Energizes when blower motor is on
Energizes when blower motor is on
Energizes when there is a call for heat
Detects air pressure from draft induced blower
Energizes the high speed on the blower motor
Energizes the humidifier motor
Provides electrical voltage reduction
Energizes to allow gas flow to burners
Energizes draft induced blower motor
Energizes humidifier circuit
Operating Circuit = 110/1/60
Control circuit = 24V
Improvise to simulate the various components (if required)
DO NOT ENERGIZE BOARD CIRCUITS UNTIL CHECKED BY INSTRUCTOR
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
21
Practical Assignment 20
Project Learning Objective
Instructor s Evaluation
1 – Working Safely
Poor
Fair
Good
2 – Knowing the Appliance
Poor
Fair
Good
3 – Recording of Proper Information
Poor
Fair
Good
4 – Proper use of testing equipment
Poor
Fair
Good
5 – Proper use of hand tools
Poor
Fair
Good
ELECTRICAL CIRCUIT READINGS
Use components from Practical Assignment 19
LOCATION
Voltage at power source
Voltage at blower motor
Ohms of blower motor high speed
Ohms of draft induced blower motor
Voltage at limit switch
Voltage at primary side of transformer
Voltage at secondary side of transformer
Ohms at primary side of transformer
Ohms at secondary side of transformer
Amperage draw of blower motor
Amperage draw of draft induced blower
motor
TEST RESULTS
Improvise to simulate the various components (if required)
Activity report and student comments
Complete?
I
c
© 2020 Appliance Technical Institute of Canada
Yes
C
No
e
22
Gas Orifice Capacity Chart
GAS USE IN BTUS PER HOUR AGAINST A GIVEN ORIFICE SIZE (DRILL SIZE)
Drill Size
Decimal
Equivalent
Gas Pressure >
Natural Gas
3.0
3.5
4.0
LP Gas
4.5
7.0
11.0
654
755
874
919
1163
1436
1583
1818
2068
2244
2427
2815
3062
3451
3518
3677
3910
4399
4654
4916
5185
5461
5745
6036
6334
6639
7764
7898
9709
10862
12712
14026
14479
16119
17594
19135
20740
21902
22127
23558
24144
26557
28442
31391
31592
33092
34485
35549
36992
38837
40726
42975
43447
44241
45849
48316
51706
56104
59290
66413
70881
70982
74456
77591
80253
82959
85157
87719
88507
90776
93074
98945
103161
106103
107465
112492
116338
118938
122891
126235
128263
130992
134443
137940
142194
145067
148114
149430
151635
156844
162906
171898
175372
186658
1273
1469
1700
1788
2263
2794
3081
3536
4024
4366
4722
5476
5956
6713
3843
7153
7607
8557
9053
9563
10087
10625
11176
11742
12322
12916
15104
15365
18888
21131
24730
27286
28167
31357
34228
37225
40347
42608
43045
45831
46969
51663
55331
61067
61460
64377
37087
69156
71964
75553
79229
83603
84522
86066
89195
93994
100588
109145
115343
129200
127992
138088
144847
150946
156123
161389
165664
170649
172181
176596
181066
192487
200690
206413
209063
218843
226324
231381
239072
245577
249522
254831
261546
268348
276625
282213
288141
290701
294991
305125
316916
334411
341169
363124
Gas Use in Btus/Hr
80
79
1/64
78
77
76
75
74
73
72
71
70
69
68
1/32
67
66
65
64
63
62
61
60
59
58
57
56
3/64
55
54
53
1/16
52
51
50
49
48
5/64
47
46
45
44
43
42
3/32
41
40
39
38
37
36
7/64
35
34
33
32
31
1/8
30
29
28
9/64
27
26
25
24
23
5/32
22
21
20
19
18
11/64
17
16
15
14
13
3/16
12
11
10
9
8
7
13/64
6
5
4
3
7/32
2
1
.0135
.0145
.0156
.0160
.0180
.0200
.0210
.0225
.0240
.0250
.0260
.0280
.0292
.0310
.0313
.0320
.0330
.0350
.0360
.0370
.0380
.0390
.0400
.0410
.0420
.0430
.0465
.0469
.0520
.0550
.0595
.0625
.0635
.0670
.0700
.0730
.0760
.0781
.0785
.0810
.0820
.0860
.0890
.0935
.0938
.0960
.0980
.0995
.1015
.1040
.1065
.1094
.1100
.1110
.1130
.1160
.1200
.1250
.1285
.1360
.1405
.1406
.1440
.1470
.1495
.1520
.1540
.1563
.1570
.1590
.1610
.1660
.1695
.1719
.1730
.1770
.1800
.1820
.1850
.1875
.1890
.1910
.1935
.1960
.1990
.2010
.2031
.2040
.2055
.2090
.2130
.2188
.2210
.2280
428
494
572
602
762
940
1037
1190
1354
1469
1589
1843
2004
2259
2303
2407
2560
2880
3046
3218
3394
3575
3761
3951
4147
4346
5083
5171
6356
7111
8322
9182
9478
10552
11518
12527
13577
14338
14485
15423
15806
17385
18620
20550
20682
21664
22576
23272
24217
25425
26662
28133
28443
28962
30015
31630
33849
36729
38815
43478
46402
46469
48743
50795
52538
54309
57748
57426
57941
59427
60931
64775
67535
69461
70353
73644
76161
77863
80451
82640
83968
85754
88014
90303
93088
94969
96963
97825
99269
102679
106647
112534
114808
122196
463
534
618
650
823
1016
1120
1285
1462
1587
1716
1991
2165
2440
2487
2600
2765
3110
3291
3476
3666
3862
4062
4268
4479
4695
5490
5585
6865
7680
8989
9918
10238
11398
12441
13530
14665
15487
15646
16658
17072
18778
20111
22197
22339
23399
24384
25137
26157
27462
28798
30388
30722
31283
32420
34165
36562
39672
41924
46961
50120
50192
52649
54865
56747
58661
60215
62027
62584
64188
65813
69965
72946
75026
75990
79544
82263
84102
86897
89261
90695
92625
95066
97538
100547
102578
104732
105663
107222
110906
115192
121550
124007
131987
495
571
661
695
879
1086
1197
1374
1563
1696
1835
2128
2314
2608
2659
2779
2956
2235
3518
3716
3919
4128
4343
4563
4788
5019
5869
5970
7339
8211
9609
10603
10945
12184
13300
14464
15678
16556
16726
17809
18251
20075
21500
23729
23882
25015
26068
26872
27963
29358
30786
32486
32843
33443
34659
36524
39068
42411
44819
50204
53581
53657
56284
58653
60665
62711
64372
66309
66905
68620
70357
74795
77982
80206
81236
85036
87943
89908
92897
95425
96957
99020
101629
104272
107489
109660
111964
112958
114626
118563
123145
129943
132569
141100
525
605
701
737
933
1152
1270
1457
1658
1799
1946
2257
2455
2767
2820
2948
3135
3527
3731
3941
4157
4379
4606
4840
5078
5323
6225
6333
7785
8709
10192
11246
11609
12924
14107
15342
16629
17560
17741
18889
19358
21293
22804
25168
25330
26532
27649
28502
29660
31139
32654
34456
34835
35472
36761
38739
41457
44984
47538
53249
56831
56912
59698
62211
64345
66515
68277
70332
70963
72783
74625
79332
82713
85072
86164
90195
93278
95362
98532
101213
102839
105027
107794
110598
114009
116312
118755
119810
121579
125755
130615
137825
140611
149659
Gas Technician Practice Questions
1.
2.
3.
4.
5.
6.
3 Hot Water Boilers each firing at 500MBH,
2Hot Water Heaters each firing at 270MBH
and 1 Domestic Hot Water Heater firing at
30MBH. Consider the grill to have 80% free
air space. What size should the grill be?
275 Square
Inches
5 Boilers with Draft Diverters are to be
installed in an enclosed Furnace Room. The
volume of the room is 15,000 Cubic Feet. The
input for each Boiler is 300,000 BTUH. What
size free air opening is required?
179" Square
Inches
A 60,000 BTUH Water Heater with no Draft
Diverter is to be installed in a closet type
enclosure and all air is to be taken from
indoors.
A 60 Square
Inch lower
opening
only
A 120 Volt Power Supply for a residential
Electrical Circuit is taken from the:
Load side of
one branch
circuit
breaker and
a Neutral
Plug
Above ground piping of which size and
larger must be welded, unless the authority
having jurisdiction allows threads
2 1/2" Inches
(75mm)
After a Direct Vent Radiant Heating System
is installed in a new house, the customer
complains that, "The Walls and Windows are
wet". What is the most reasonable response?
Recommend
the
installation
of a
Mechanical
Ventilation
System
13.
Aquastats respond to changes in:
Water
Temperature
14.
As Flow Rate increases, the pressure
difference across a Water Pump
Decreases
15.
As the length of a Conductor Increases,
the Voltage Drop along the Conductor:
Increases
16.
As the length of an Electrical run
increases, it may be necessary to
Increase the
Wire Size
17.
As the number of occupants in a tightly
constructed building increases, the:
Relative
Humidity
Increases
18.
As the Outlet Temperature decreases
from a Water Heater to the Heating Loop
in a Combination Heating System, the:
Heating Output
from the Air
Handler
Decreases
19.
As the temperature of a Thermistor
increases, the Current Flow through it...
Increases
20.
A Backflow Prevented used in a Boiler
System should be located in the:
Make up Water
Line to the
system
21.
A Backflow Prevented used in a Boiler
System should be located in the
Line connecting
the Boiler and
Cushion Tank
22.
Before firing a Gas Burner in a Steam
Boiler System, What must be done?
Check for
enough Water
23.
The best way to remove odours from a
house is to:
Ventilate the
house
24.
A Blue Flame is the result of
mixingbPrimary Air with Gas prior to
Ignition. What is this type of Flame
referred to as?
A Bunsen Flame
7.
Air enters a House through a process called...
Infiltration
8.
Air filtration devices are generally located in
the:
Return air
plenum
9.
All Storage Water Heaters are required to
have:
High Limit
Aquastat
and
Temperature
Relief Valve
25.
The Branch Fuse Size is determined by:
The Wire Size
26.
Brazing Rods with ___________ should not be
used for Natural Gas/Propane as it reacts
with the sulfur in the fuel making the
Brazed joint brittle
Phosphorus
10.
An Anti Scald Device is installed to keep
temperatures below:
140 degrees
Fahrenheit
27.
A British Thermal Unit is the amount of
Heat required to:
11.
An appliance rated over 400,000 BTUH is
installed in a Boiler Room. The combustion
Air Opening is calculated to be 90 Square
Inches. What size Ventilation Air Opening is
required?
10" Square
Inches
Raise the
temperature of
one pound of
Water by one
degree
Fahrenheit
28.
No
An Appliance Vent shall terminate from any
building Mechanical Air Inlet by at least:
6' Feet
Can a Shut-off Valve be installed
Upstream of a Relief Valve to allow for
the removal of the Relief Valve for
servicing without having to empty the
contents of a tank?
12.
29.
Circulating Pump are calculated (sized)
according with:
Water Flow
and Head
Pressure
30.
The Clearance to Combustible Appliance
required for a Free Standing Room Heater
is:
36" Inches
31.
The Closing Force in a Gas Pressure
Regulator is the:
Pressure
Downstream
of the
Regulator
32.
The Closing Force in a Regulator is called:
Downstream
Pressure
33.
A Combination System Burner is activate
for what
A Room
Thermostat
34.
A Commerical type Dryer shall have a
minimum _____ front clearance from
combustible material
18" Inches
The components of a Copper Fin Tube,
Instantaneous Water Heater are a/an:
Pump, Pump
Control,
Flow Switch,
Temperature
and Pressure
Relief Valve,
and a Limit
Control
35.
36.
Condensate in the Boiler Heating System is:
Water in a
Steam Boiler
return line
37.
Convection is:
Heat transfer
through
Fluids
38.
A customer complains that the pilot goes
out every once in a while. This is the second
service call for this problem this month.
When the pilot is reestablished, the closed
circuit millivolt test stays steady at 14mV,
the magnet drops out at 4mV, What should
be done next?
Check for
another
problem
such as
Down Draft
or Pilot
Position
Cylinders at Construction Sites shall be
stored outdoors in an area that provides
protection from tempering. The total
quantity of Propane stored shall not
exceed:
1000lb
40.
Direct current travels how:
In one
direction
41.
The discharge piping from the Temperature
and Pressure Relief Valve on a Water
Heater shall terminate not more than _______
from the floor
12" Inches
39.
42.
A domestic Air Conditioner,
What is the minimum Supply Air
in CFM per ton of Cooling
required?
400
43.
An Electrical Pictorial Diagram
is used to:
Show component location
44.
The External Bypass Valve in a
Gas Pool Heater is set by:
Determining the
Temperature Rise across
the appliance
45.
The External Bypass Valve is
set by:
Determining the
Temperature Rise across
the appliance
46.
The external Static Pressure of
Supply Air Plenum on a Force
Air Furnace should be between
0.2" to 0.5" W.C. (Water
Column)
47.
A Fan Control is a:
Normally Open
Temperature Control that
Closes on Temperature
Rise
48.
Final drawings on a Job are
called:
As Built Drawings
49.
A Fire Tube Boiler has:
Water outside the Tubes
and Flue Gases inside
50.
The Flow Rate of the Water
passing through a Heating Coil
of an Air Handler is controlled
by the:
Balancing Valve on the
Heating Loop
51.
From the following list, What is
the most probably cause of a
service callwhere a Combustion
Gas Odour is detected in the
heated space whenever the
Circulatiing Blower activities?
Cracked Heat Exchanger
52.
From the following list, which
action will have the greatest
effect on reducing mold growth
in a house?
Covering earthen floors
and open water surfaces
(stumps, aquariums etc.)
Open stumps and earth
floors and will introduce
a ton of humidity into the
house
53.
From the following, What is is
equivalent to 28" W.C?
1 PSIG
54.
Fuses serving motor circuits
should be of
Time Delay Type
55.
Gas Meters must be maintained
in the Upright Position...
At all times, including
when connected for
service
56.
The Gas Meter Test Dial can be used
for:
Checking the Input
of an Appliance
57.
Gas Tanks after ________ must be
regulated by Transport Canada
1991
58.
Gross Stack Temperature is the Flue
Gas Temperature:
Upstream of the
Draft Hood
59.
Ground Fault Circuit GCF protects
loads
Served for that
Breaker
60.
Ground Fault Circuit Interrupter (GFCI)
protects of shock in:
Damp and wet
conditions
61.
A gurgling sound coming from a firing
Water Heater may be a symptom of:
A situation where
Deliming is
required
62.
A hard sharp small flame indicates:
Small Orifice
63.
Head Pressure in a Piping System for
Hot Water Heating is
The resistance of
the entire piping
system measured
in Feet of Water
64.
Heat Conduction is:
Heat transfer
through solid
objects
65.
The High Limit Switch in the Circuitry
of a Conventional Furnace is wired in
Series with the:
Gas Valve
66.
A high Pressure Line of Natural Gas is
above:
2 PSIG (Clause
6.3.3 & Table 6.1)
67.
The High Temperature Limit Switch in
the Circuitry of a Conventional
Residential Furnace is wired in series
with the:
Gas Valve
68.
A Hot Surface Igniter requires how
many volts to operate properly ?
115 to 125 VAC
69.
Hot Water Boilers used to Supply
Water for Commercial and Industrial
Hydronic Spaces Heating System are
usually operating at
250 degrees
Fahrenheit and 160
PSIG
How are excessive levels of ozone
produced?
Insufficient air flow
71.
How are Manual Shut Off Valves
connected to piping?
Flanged
72.
How far should a Dryer Moisture
Exhaust Duct terminate from a Service
Regulator?
36" Inches (Clause
7.7.4.)
73.
How is a High Limit tested on a Force
Warm Air Furnace?
By disconnecting
the Air Circulating
Blower
70.
74.
How is a Pressure
Switch tested to see
if it is defective?
With the Power Off to the furnace,
remove the Electrical leads from the
switch. Connect a Meter across the
Switch, Reset and if there is no
Continuity, the switch is defective
75.
How is the Heat
Anticipator setting
determined for a
Thermostat with an
adjustable
Anticipator?
By measuring the current drawn by
the components in the circuit being
feed directly by the Thermostat
76.
How long may a
Corrugated Flexible
Connector be when
installed on a range?
6 Feet
77.
How many Duct
openings are
required for a Bypass
Humidifier?
Two
78.
How often should
Oxygen Regulators
be oiled?
Never
79.
The "Hydrogen
Evolution" in a Water
Heater Tank is
caused by:
Highly Acidity Conductive Water
80.
If 1 Cubic Foot of
Natural Gas is 1000
BTUH, What is the
ratio of Combination
Air?
10
81.
If 1 Cubic Foot of
Natural Gas is 1000
BTUH, What is the
ratio of Dilution Air?
15
82.
If 1 Cubic Foot of
Natural Gas is 1000
BTUH, What is the
ratio of Excess Air
5
83.
If 1 Cubic Foot of
Natural Gas is 1000
BTUH, What is the
ratio of Total Air
30
84.
If 1 Cubic Foot of
Propane Gas is 2500
BTUH, what is the
ratio of Combustion
Air?
25
85.
If a belt on a Blower is too tight, What will
happen to the Blower Motor Current?
Increase
86.
If it has been determined that a Steam
Boiler Burner is on and the Water Gauge
glass indicates no water, What should be
done immediately?
Shut off Fuel
Supply
87.
If resistance of a Wire increases:
Temperature
increases
88.
If the By-Pass Valve is closed in a Gas
Heater, which is the most probably effect?
It will cause
Condensation
89.
If the Fan Compartment door of an
appliance is left of the motor:
Current will
increase
90.
If there is gurgling sound from the Hot
Water Tank, the most probably cause is
Scale or Lime
built-up due
to water
hardness
91.
If the Relative Humidity of a room is
increased, the Temperature in the room
must be increase to maintain the same
level of comfort.
False
If the Supply Pressure excess the working
pressure of the Water Heater Tank, you
must install:
A Pressure
Reducing
Valve
If the Vent Motor fails, this component will
shut off the Gas Valve and the Gas Flow
stops:
Air Pressure
Switch
94.
If too many Lava Rocks are placed in the
rack of a barbeque:
The Burner
will burn out
prematurely
95.
In a Circulating Water Heater, the outlet
Temperature of the system is controlled
by:
Storage Tank
Thermostat
96.
In a Gas Regulator, Which is the Loading
Element
The spring
97.
In a Gas Regulator, Which is the Restricting
Element?
The valve
disk
98.
In a particular Installation, the required Air
Supply opening is 50 Square Inches. When
using a grill rated at 75% free area, What is
the rough opening?
66.6" Square
Inches
99.
In applications with frequent operation of
throttling of Water Flow you would use:
A Globe
Valve
100.
In a Propane Gas System with more 5
PSIG, the Line Relief Valve must be set to:
1.5 to 2 times
the Normal
Pressure
92.
93.
101.
In a Steel Fire Tube Boiler:
The Flue Gases
flow through the
Steel Tubes and
transfer Heat to the
Water surrounding
them
102.
In domestic Heat Pump applications,
What is the minimum Volume of
Supply Air (cfm) per ton of Cooling
required?
450
103.
An inline Ammeter is connected
In series with the
device being
checked
104.
In order to prevent condensation
from forming on the outside of a duct,
the duct must be:
Insulated on the
outside
105.
In Residential Water Heaters , the
High Limit Aquastat is set to operate
at:
190 degrees
Fahrenheit
106.
The instrument used to determine
Potential Difference in an Electrical
Circuit is the:
Voltmeter
107.
In Tanks of Propane, the Hydrostatic
Pressure Relief Valve will be not less
than:
375 PSIG
108.
Is it permissible to use the Propane
side of a Refrigerator in a
Receational Vehicle while in the
vehicle is in motion?
No
109.
It has been determined that a Free
Air Opening of 152" Square Inches is
required for an installation. How large
would the opening have to be if the
grill has 75% Free Area?
203" Square Inches
110.
It is permissible to use gas piping as
an Electrical Ground if:
It is used in the
Flame Safeguard
Circuit
111.
The larger Cylinder used for Propane
is:
420lb
112.
A Leak Limiting Device on a
regulator:
Allows a
controlled, safe
amount of leakage
if the Diaphragm
ruptures
113.
A Low Pressure Steam Boiler
operates at pressures of
15 PSIG
114.
A Low Water Cut Off Device on an
automatically fired Hot Water Heating
Boiler rated at 350,000 BTUH (102kW) is:
Required when
any portion of
the Circulating
System is
located below
the Boiler
127.
The most important element
required for proper combustion in
a gas appliance is:
Air
128.
The most likely cause of an
Intermittent Hissing Sound "like
water dripping on a something
hot" coming from a Water Heater
is:
Condensation in the
Flue Passage caused
by drawing Water from
the Tank when the Hot
Water has been
depleted
129.
Most residential Water Heaters
are set to operate at:
130 degrees Fahrenheit
130.
Most thermostatically controlled
Domestic Hot Water Heaters
utilize:
Rod and Tube sensing
115.
A Low Water Cut Off Device onnan
automatically fired Hot Water Heating
Boiler rated at 450,000 BTUH is:
Always required
116.
The main purpose of the Building Skin is
to:
Protect the
underlying
materials
117.
The marks required on a Propane
Cylinder are:
Water Capacity
and Tare Weight
118.
The maximum pressure allowed in a
Cylinder of Propane is:
375 PSIG
131.
Hydrostatic Relief
Valve
119.
The maximum pressure loss between
the termination of the utility installation
and an appliance for piping system with
supply pressure in excess of 14" W.C.
shall not exceed
1.0" W.C. (0.250
kPa)
A _______ must be installed
between 2 Shut Off Valves in a
Propane System:
132.
Appliance Regulator
Millivolt wiring should be isolated from
Line Voltage Wiring because:
The Line Voltage
will induce a
Voltage into the
Millivolt Wiring
Name of the Regulator used in a
Combination Gas Valve used to
reduce the building Gas Pressure
to the correct burner working
pressure:
133.
A Natural Gas Service Regulator
is normally set to deliver
pressure from:
Pounds to 7 Inches
W.C.
Millivolt wiring should be isolated from
Line Voltage Wiring because
The Line Voltage
will induce a
voltage into the
Millivolt Wiring
134.
Net Stack Temperature is the Flue
Gas Temperature:
Minus the Ambient
Temperature
135.
The normal fuse for a #14 AWG
copper Conductor is:
15 Amps
136.
On an Electrical Schematic, all
operating controls are drawn:
Normally Open
137.
On an Electrical Schematic
Diagram, the safety controls are
typically drawn:
To the Left of the Loads
138.
The oncoming Power Supply to
residential homes is:
240/1/60
139.
A One Cubic Foot Test Dial on a
Natural Gas (NG) meter makes
One Revolution every 22
seconds. Approximately how
many BTUH are being
generated?
164 MBH
140.
A One-Half Cubic Foot Test Dial
on a meter makes One
Revolution every 22 seconds.
Approximately how much Heat is
being generated?
82,000 BTUH
120.
121.
122.
The minimum allowable distance to be
maintained from a 50,000 BTUH Water
Heater Flue Outlet to grade level is
12" Inches
(Clause 8.18.8(f) )
123.
The minimum distance to the floor (high)
to install a Furnace in a Repair Garage
is 54" Inches (4.5' Feet ) Clause 4.16.3
...
124.
A Monitor Regulator is:
A redundant
Regulator used
to monitor a
working
Regulator
125.
The most accurate way to determine
the amount of Propane in a Large
Storage Tank is by the use of a:
Roto Guage or
Slip Tube Guage
126.
The most effective way to prevent
Lime-Scale deposits in Water Heater
Tanks is
Installing a
Water Softner
141.
The open Circuit Test reading of a
Thermocouple should be in range of:
25mV to 30mV
156.
The Relief Valve for a Low Pressure Hot
Water System should be set at:
30 PSIG
142.
Plate Humidifiers operate:
All the time the
fan is running
157.
The Relief Valve for a Low Pressure Steam
System should be set at:
15 PSIG
143.
A poorly insulted house may result in:
Increased fuel
consumption
158.
144.
A Pressure reading of 14.7 Pisa is
equivalent to
0 psig
Residential Hot Water Boilers used in
Hydronic Heating System are usually
operating at
180 degrees
Fahrenheit
and 15 PSIA
159.
Pressure Reducing Valve:
Reduces the
City Main
Pressure to a
safe Working
Pressure
The Residential Water Heater, the ECO is set
to operate at:
200
degrees
Fahrenheit
160.
The resistance of a Thermistor... as its
temperature rises
Decreases
161.
A Schematic Diagram shows the safety
controls:
To the Left
of the loads
162.
Separate Heating and Cooling, therefore
Double Pole and Double Stage for Heating
and Cooling therefore Double Throw. Which
of the following heating systems would be
expected to cause problems due to the
"Distribution Effect"?
A Forced
Air Furnace
with a
return air
opening in
the furnace
room
163.
Single Wall Vent Connectors:
Shall not
pass
through
Floors,
Ceilings or
Roofs
164.
State Ohms Law?
Current =
Voltage /
Resistance
165.
Steel Boiler are generally classified as
Water Tube
Boilers
166.
Switches are rated:
By the
Amperes
167.
A switch in the Neutral Line can be used:
Never
168.
A tank of Propane shall have a Maximum
Allowable Working Pressure (MAWP) of not
less than
250 PSIG
169.
The Temperature of the Water returning
from the Heating Loop in a Combination
System employing a Water Heater for
Domestic Hot Water Heater and Space
Heating must be:
Lower than
the
minimum
Temperature
required to
activate the
Burner
145.
146.
A Pressure Regulator is a device that:
Reduces Gas
Pressure from
Inlet to Outlet
147.
The Pressure Relief Valve for Low
Pressure Hot Water systems should be
set at:
15 PSIG
148.
A Propane Gas unit termination of a
opening in a RV or Motor-Home must
be minimum of:
36" Inches
149.
Propane supply in Industrial Buildings,
the Maximum Pressure allowed is
20 PSIG
150.
The purpose of a Thermal Expansion
Tank is
To keep Water
Pressure stable
in the system as
the Temperature
Rises
151.
The purpose of installing a Balancing
Valve in a Combo Heating System is
Control and
Balance the
Water Flow
through different
zones or
branches
152.
Radiant Heat is:
A wave form of
heat transfer
153.
The range of Voltage in the Voltage
section or Power section of an
Electronic Air Cleaner (EAC) is?
7,500 to 8,500
VDC
154.
A receptacle mounted Ground Fault
Circuit Interrupted protects against:
Current Flow to
Ground
155.
The recommended range of Relative
Humidity in a house to control Indoor
Air Contaminates, increase comfort, and
maintain the structural integrity of the
house is:
30% - 50%
170.
Temperature rise, as it applies to Hot Water
Heating is
Water
Temperature
difference
across the
Heater
171.
"Temperature Rise", When applied to a Hot
Water Heater is the:
Water
Temperature
difference
across the
Heater
172.
There are two appliances in a 10ft x 10ft x
20ft structure which has an equivalent
leakage area greater than 0.05 square
meters. A furnace has a draft hood and input
of 50,000 BTUH. The second appliance has
an input of 75,000 BTUH, and does not have
a draft hood. The required combustion air
opening size is:
9 Square
Inches
(5800 mm2)
There is a new Forced Air Furnace equipped
with an induced Draft Fan beside a
conventional Water Heater in a basement.
The customer has decide enclose the area to
make a separate furnace room. The house is
approximately 25 years old and has a door
separating the basement from the upper
levels. Furnace input is 100,000 BTUH with
AWH input of 25,000 BTUH. The enclosure is
10ft x 20ft x 7ft. The structure dimension are
20ft x 30ft x 7ft x 3 levels. What size
opening will be required in the furnace room
door for combustion air?
125 Square
Inches
There is a no Heat call for the system, Using
the following...
Thermostat
173.
174.
Terminals at the Thermostat reads 24 Volts
Gas Valve Coil reads 0 Volts
Gas Coil to Gas Coil common reads 24 Volts
Points across High Limit read 0 Volts
176.
There is a no Heat call for the system, Using
the following...
Thermostat terminals read 0 Volts
Gas Valve Coils terminals read 0 Volts
High Limit terminals read 110 Volts
L & N terminals read 110 Volts
Determine which component is open:
Gas Valve
Coil
Thermostat terminals read 0 Volts
Gas Valve Coil terminals read 24 Volts
Gas Valve (Thermostat side) to common
terminals read 0 Volts
Gas Valve (Transformer side) to common
terminals read 24 Volts
Determine which component is open:
177.
A Thermocouple produce a maximum of:
1 Volt
178.
A Thermopile or Powerpile generates:
Hundreds
of
Millivolts
179.
A Thermostat serving a unit which has
separate Heating and Cooling Control
transformers and has One Stage of Heating
and One Stage of Cooling is a... control
DPDT
(Double
Pole
Double
Throw)
180.
A Thermostat with a Single Mercury Bulb
which controls a Single Stage Heat, Single
Stage Cool unit is a... control
SPDT
(Single
Pole
Double
Throw)
181.
Three Hot Water Boilers, each firing at 500
MBTUH. Two Hot Water Heaters each firing at
at 270 MBTUH and a domestic Water Heater
firing at 30 MBTUH. Determine the required
grill size, assume to have 80% free air space
275"
Square
Inches
182.
Two Hot Water Boilers each firing at 750,000
BTUH, 1 Water Heater firing at 270,000 BTUH
and 1 Water Heater firing at 30,000 BTUH.
These appliances are contained in a room with
a cutout and a grill with 80% free area. What
size in square inches should the grill be?
250
Square
Inches
183.
Two undesirable products of Incomplete
Combustion are:
Carbon
Monoxide
and
Aldehydes
184.
The Unitrol used in a Residential Water Heater
Tank is designed to:
Shut off
the Gas
Flow if the
pilot goes
out
185.
Vapour Barriers should be installed on:
The warm
side of the
insulation
Determine which component is open:
175.
There is a no Heat call for the system, Using
the following...
High Limit
186.
The Ventor Motor on a Power Vent Water
Heater fails, this component prevents
operation
Pressure
Switch
199.
What is the allowable maximum
distance Piping supports should be
spaced on a 4" Inch Gas Line?
15 Feet (4.5m)
187.
Voltmeter is connected:
In Parallel
with device
tested
200.
What is the apprompximate
secondary voltage range of an
Electronic Air Cleaner?
9,000 - 12,000
Volts
188.
A Water Heater with a Draft Diverter is to
be connected to a Masonry Chimney using a
Single Wall Vent Connector. The Vent
Connector rise "R" will be 2 Feet, "H" is
determined to be 25 Feet, the Water Heater
is rated at 50,000 BTUH and will be located
3 Feet from the Chimney. Determine the
Vent Size and maximum input of the Vent if
the house is 25 years old. (Do not use
interpolation)
4" Inch
diameter, 67
cfh
201.
What is the best method of Adjusting
and Setting the Pressure on an
Appliance Regulator?
Adjusting the
Regulator Set Point
using a Manometer
to the Appliance
Rating
202.
What is the boiling point of Natural
Gas (the point at which it changes
from a liquid to a gaseous state)?
-258 degrees
Fahrenheit
203.
C2H2
Water Jackets allow water to Circulate from
section to section in:
Cast Iron
Boilers
What is the chemical formula of
Acetylene?
204.
5.17 Feet (1.5m)
The weight of gas compared to the weight
of an equal Volume of Air is known as the
specific gravity of gas. What is specific
gravity of Propane Gas?
1.52
What is the equivalent of a 2" Inch
NPS Schedule 40, 90 Degree
Threaded Elbow?
205.
What is the explosion limits for
Natural Gas?
4 to 15%
The weight of gas compared to the weight
of an equal Volume of Air is known as the
specific gravity of gas. What is the specific
gravity of Natural Gas?
0.60
206.
What is the explosion limits for
Propane Gas?
2.4 to 9.5%
207.
What is the flame speed for Natural
Gas?
12 inches / sec
The weight of Liquid Propane is compared to
the weight of an equal Volume of Water is
known as the Specific Gravity of Liquid
Propane. What is the Specific Gravity of
Liquid Propane?
0.51
208.
What is the flame speed for Propane
Gas?
11 inches / sec
209.
What is the flame temperature for
Natural Gas?
3600 degrees
Fahrenheit
What additional component must be
installed in Combination System in order to
stable the Water Pressure:
An
Expansion
Tank
210.
What is the flame temperature for
Propane Gas?
3600 degrees
Fahrenheit
211.
What are the main components of a GasFired Refrigerator?
Generator,
Evaporator,
Absorber,
Condenser
What is the ignition temperature for
Natural Gas?
1300 degrees
Fahrenheit
212.
What is the ignition temperature for
Propane Gas?
920 degrees
Fahrenheit
213.
195.
What device is used to prove a Dryer Motor
is running?
Centrifugal
Switch
What is the main cause for the Stack
Effect in a Residential Water Heater?
Short draws of
Water
214.
What does a Pictorial Diagram show?
The
components
location
What is the maximum clearance from
the sides of a Domestic Range to
combustible materials, unless
otherwise specified?
6 Inches
196.
197.
What happens to the system in the cooling
mode if the prefilter is an electronic air gets
plugged with dirt?
The Cooling
Coil frosts
215.
65 PSIG (Clause
5.1.1. & Table 5.1)
198.
What is 0.5 psig in "inches W.C."?
14" W.C.
What is the maximum Gas Pressure
which can be supplied (Natural Gas)
to a mechanical room located on the
roof of a Commercial Building
189.
190.
191.
192.
193.
194.
216.
What is the Maximum Outlet Pressure for a
Second Stage Regulator on a Residential
Propane Tank System
11" W.C.
(Water
Column
)
229.
What is the minimum size of the combustion
air opening from outdoors for an appliance
without a Draft Hood and with an input of
50,000 BTUH installed installed in a
structure which has an equivalent leakage
area greater than 0.05 m2 and dimensions
of 10ft x 10ft x 20ft?
0 Square
Inches
217.
What is the maximum permitted filling density
of a cylinder with Liquid Propane (Relative
Density = 0.51) by Liquid Volume?
80%
218.
What is the maximum supply pressure allowed
in a Single Family Dwelling downstream of the
utility termination?
2 PSIG
230.
What is the minimum Time and Pressure
required to test a new welded 4" NPS
piping system that is 100 Feet long with
supply pressure of 5 PSIG?
24 hours at
50 PSIG or
1.5 times the
maximum
operating
pressure,
whichever is
greater
219.
What is the minimum clearance from the sides
of a Domestic Dryer to combustible materials,
unless otherwise specified?
6 Inches
220.
What is the minimum Clearance to
Combustibles from the top of the Plenum of a
Converted Forced Warm Air Furnace?
1" Inch
231.
What is the normal return air requirements
for Forced Air Furnace?
900
221.
What is the minimum closed Thermocouple
reading?
10mV
232.
What is the normal Supply Air volume for
Forced Air Furnace in cfm?
700
222.
What is the minimum distance above a Flat
Roof that a Vent can terminate if it is 8 Feet
horizontally from an adjoing building which is 4
Feet higher than the top of the Building on
which the Vent is located.
6' Feet
233.
What is the primary component of Natural
Gas?
Methane
(CH4)
234.
3' Feet
On the
Supply Air
Side
223.
What is the minimum distance that the Vent
from a 75,000 BTUH Category 3 Furnace may
terminate from a door?
What is the recommended location for a
Cooling Coil on a Suspended or Horizontal
Furnace?
235.
24" Inches
(2 Feet)
224.
What is the minimum distance that the Vent
from a 175,000 BTUH Category 3 Furnace may
terminate from a door?
3' Feet
What is the required minimum distance
Plastic Piping or Tubing must be installed
under a Commercial Parking Lot?
236.
What materials are approved for joining
Single Wall Vent Connectors?
Sheet Metal
Screws
225.
What is the Minimum Service Clearance in front
of a Boiler?
48"
Inches
237.
What must be done if cracks are discovered
in the Heat Exchanger of a Furnace?
226.
What is the minimum service clearance vertical
of a Boiler?
24"
Inches (2
Feet)
Replace the
Heat
Exchanger
238.
What must be done to Piping or Tubing
passing through concrete?
It must be
sleeved
227.
What is the minimum size of a Combustion Air
Opening from outdoors for an appliance
without a Draft Hood and having an input of
125,000 BTUH installed in a structure that has a
continuous Vapour Barrier and has an
equivalent leakage area of 0.05 m2 at a
differential pressure of 10 parcels and
dimensions of 10ft x 10ft x 20ft?
9 Square
Inches
239.
What must be done to Piping or Tubing
passing through concrete?
It must be
Double
Wrapped
240.
What must be ensured before electronic
cells are removed for cleaning?
Cells must
be deenergized
and
discharged
What is the minimum size of a Single Wall Vent
Connector which could be used for a Single
Natural Draft Appliance having an input of
1,000,000 BTUH where the Vent Connector
length is 20 Feet and the Chimney height is 50
Feet
12" Inch
Diameter
228.
241.
What of the following methods is
correct for the leak testing when
you are replacing an existing Gas
Water Heater?
Soap or Leak
Detection Device
and a 10 minute Dial
Test at normal
working pressure
(Clause 6.22.3)
242.
What protects a Stem Boiler if the
Condenstate Pump fails to return
water to the Boiler:
Low Water Cut Off
243.
What shall be provided in the Gas
Supply Line to Boiler Room or
Confined Area where the total
input of the appliance is in excess
of 2,000,000 BTUH (585 kW)?
An Identified
Accessible
Emergency Manual
Shut Off Valve
244.
What should be done if a Relief
Valve is leaking?
Replace the Relief
Valve and check for
the cause of the
activation
245.
What size conductor is required to
Bond Gas Piping?
6 AWG
246.
What size of wire should be used as
a Tracer Wire?
16 Guage
247.
What substance is added to Natural
Gas to provide an odour to it?
Mercaptan
248.
What Temperature is a joint
considered to be "Brazed"?
1000 degrees
Fahrenheit
249.
What type of Burner is used in
Conversion Burners?
Inshot and Upshot
Burners
250.
What type of Control Valve will
provide an infinite number of Firing
rates between Low Fire and High
Fire?
A High Cycle Rated
Valve
What type of Flux should be used
when Brazing Copper Tubing for
Propane System?
Non-Corrosive Type
252.
What type of room heater may be
installed in a Bathroom?
Direct Vent
253.
What type of Vent must be used
when the Vent of a Wall Furnace
will be concealed in a partition
wall?
BW Vent
What will be the result if too large
a Fire Pot is used in a Converted
Furnace or Boiler?
There will be poor
efficiency
251.
254.
255.
What will the result be if the 24 Volt
Transformer for a Power Humidifer is
wired in Series with the Humidistat and
the Humidifier Motor?
The Humidifier
Motor will
operate
properly
256.
When a Baffle is required to prevent the
direct entry of rain into an air supply
opening, by how much can a Baffle
reduce the required free area opening?
0%
257.
When a Draft Control is required, Which
of the following appliances would utilize
a Single Acting type Draft Regulator?
An Incinerator
258.
When a Gas Fired Appliance is vented
into a chimney flue serving an appliance
which burns a solid fuel in a Commercial
or Industrial application, How shall the
Vent from the Gas Appliance be
installed?
Through a
separate Flue
opening above
the Flue Pipe
connection from
the other
appliance
259.
When a new appliance is to be installed
in a typical residential basement and
the Supply Wiring to it is concealed,
which of the following types of wire is
acceptable, and most cost effective
NMD
260.
When checking a circuit of unknown
Voltage using an analog meter with 030V, 0-125V, 0-250V, and 0-600V, which
scale should be selected
0-600V
261.
When determining the position of an Air
Handler and a Water Heater to be
connected for Combination Heating
use, the most important factor to
consider from the following list is:
Venting of the
Water Heater
262.
When diluting Muriactic Acid with Water:
Add the Acid to
the Water
263.
When installing a 2" NPS piping system
in a commercial establishment and
branch connections are required for
unkniwn additional future appliances.
What size must the branch outlet be?
2" Inches
264.
When is it necessary to Purge every
branch supply line of a piping system?
Always
265.
When is it permissible to use Bushings to
reduce piping size?
Never
266.
When Propane is to be used in the
Construction Repair or important of a
building, How many 100lb cylinders may
be manifolded together and used
indoors?
3
267.
When should a Relief Valve
on a Regulator operate?
When there is excessive
Pressure in the Supply Piping
268.
When sizing either a Vent or
a Chimney which will vent
more than one Natural Gas
Appliance, Which of the
following could be used in
determining the size of the
Common Vent?
The area of the Common
Vent shall equal area of
either the largest Draft
Control Device Outlet or the
largest Flue Outlet plus 50%
of the sum of the outlet
areas of the additional
appliance
When the Circulating Pumps
Impeller has Air in it, this
issue is known as:
Pump Cavitation
When the installation of an
Appliance constitutes a
conversion from another
form of Energy to Gas, the
installer must:
Advise the user in writing of
the procedures to be
followed to discontinue the
Supply of the former form of
energy
When the Voltage has been
determine to be
approximately 120 volts,
which scale on an analog
meter should be selected
for most accuracy?
0-250 Volts
When two 10 microfarad
capacitors are connected in
Parallel, What is the net
result?
20 mf
When two 10 microfarad
capacitors are connected in
Series, What is the net
result?
5 mf
When two 10 ohm resistors
are connected in Parallel,
What is the net result?
5 ohms
275.
When two 10 ohm resistors
are connected in Series,
what is the net result?
20 ohms
276.
When using a Flue Gas
Analyser which measures
CO2 and you are in doubt as
to the accuracy of the
reading, How would you
verify the accuracy of the
instrument?
By comparing it to a known
sample
When using an Ohmmeter,
the most important thing to
remember is to:
De-engerize the Circuit
269.
270.
271.
272.
273.
274.
277.
278.
Where is installed the Circulation
Pump in a Hydronic System?
Circulation Pumps are
installed at the Point
of No Pressure
Change
279.
Which control will shut off the
Gas Valve if the Vent Motor does
not work in a Natural Gas
Furnace?
High Limit Switch
280.
Which device shuts off the Spark
Igniter in a Spark Ignition Dryer
after proper ignition?
Ignition Sensor
281.
Which instrument is used to
determine the speed of a Direct
Drive Fan Motor?
A Tachometer
282.
Which is the most common cause
of Flue Gas Spillage from gas
appliances?
Negative Air Pressure
caused by Mechanical
Systems
283.
Which method of jointed Steel
Piping used for Natural Gas
Systems is NOT acceptable?
Flared fittings
284.
Which of the following applies if a
Furnace is used for temporary
Heat in a Residence under
construction?
The Furnace must be
installed on a finished
concrete floor or slab
at least 4" thick and 6"
larger than the base of
the furnace
285.
Which of the following are used in
an Absorption Refrigeration
cycle?
Ammonia and
Hydrogen
286.
Which of the following is
acceptable when a Fireplace
insert is installed?
A Metal Chimney Liner
287.
Which of the following is required
to determine the size of a
Circulator Pump to be used on a
Combination Heating System
employing a Water Heater?
The required Water
Flow Rate and the
Head Pressure in the
complete Heating
Loop
288.
Which of the following is the best
procedure to increase the
Furnace Blower Speed?
Close up the Motor
Pulley
289.
Which of the following
statements is correct concerning
a Combination Heating System
employing a Water Heater to
supply Domestic Hot Water
Heater and Space Heater?
Isolation Valves
should be installed in
both the Supply and
Return Line of the
Heating Loop
290.
Which of the following types of
wire must be used in Damp
locations?
NMW
291.
Which tool is used to determine if the windings on an Electric Motor have shorted?
Ohmmeter
292.
Why a Relieve Valve is used in a Gas Regulator?
To ensure the exit
pressure is not exceeding
the Design Pressure
293.
Why is a Low Limit Control used in Combination System?
To assure a constant
supply of Hot Water
294.
Why is a Low Limit installed in a Combination System?
To protect the system of
Low Temperatures
295.
Why is a Pressure Relief Valve installed in a Hot Water System?
To prevent damage in the
system
296.
A Yellow Flame is the result where there is no Premixing of Primary Air with Gas prior to Ignition.
What is this type of Flame called?
A Luminous Flame
297.
You are replacing an old Natural Gas Fired Furnace, the old furnace was firing at 140 MBTUH. The
heat loss calculations determined that the house, 1200 Square Feet required 45 BTUH per Square
Foot. What size Furnace should be installed?
75 MBTUH
298.
You are replacing an old propane fired Warm Air Furnace. The new furnace will be fired at 100
MBTUH, with a blower moving 1400 chm. What size return air duct should be installed on this New
Furnace?
12" x 24"
299.
Zero governor are designed to:
Deliver an Outlet
Pressure equal to
Atmosphere
300.
A zero governor is used primarily for:
Conversion burners
301.
A zero Ohmmeter reading taken between the casing of a Solenoid and a disconnected Wire to the
Solenoid indicates that
The coil is shorted to the
casing of the device