Chapter 1 Gas Fuels
1. The specific gravity of propane results in:
quick dasipation.
b. high ignition temperature.
c. high flammability limits.
d. pooling
Correct answer: d
2. Which of the following statements is true about the relationship between natural gas and
propane
a. Natural gas has a higher heat value than propane
b. Propane has a higher ignition temperature than natural gas
Propane has a higher specific gravity than natural gas
d. Natural gas requires a higher air to fuel ratio than propane
Correct answer: c
3. What is the ideal combustion ratio for natural gas combustion?
4 to 1
b. 10 to 1
14 to 1
d. 24 to 1
Correct answer b
4. What is the term used to describe the percentage of fuel gas in the fuel and air mixture that
will support
combustion?
a. Heat value
b. Flammability limits
c. Ignition temperature
d. Specific gravity
Correct answer: b
5. What is the name of the safety odorant added to gas for protection against undetected gas
leaks!
Aldehydes
b. Mercaptan
Sulfur
d. Methane
Correct answer: b
Chapter 2 | Principles of Combustion
1. Which of the following statements is true about carbon monoxide (CO) detection?
The presence of aldehydes does not necessarily mean that CO is present.
b. CO can be present without the detection by smell of aldehydes.
CO is never present when aldehydes are detected.
d. The presence of aldehydes will cause a residential CO
monitor to alarm.
Correct answer: b
2. Which of the following is responsible for producing yellow flame in gas hearth appliances?
a. Increased primary ait, reduced secondary air
b. Reduced primary ait, increased secondary air
c. Reduced primary air, reduced secondary air
d. Increased primary air, increased secondary air
Correct answer: b
3. A 30,000 Btu appliance is installed at an elevation of 5,000 feet above sea level. The
manufacturer requires a derating of 4% for each 1,000 feet above sea level for appliances
installed higher than 2,000 feet above sea level. What is the proper Btu input of the appliance
for
this installation?
a. 24,000
b. 26.400
c. 28,800
d. 30.000
Correct answer a
4. Which of the following catt result from incomplete
combustion?
a. Lower ignition temperature
b. Soot
c. Improved efficiency
d. Lower carbon monoxide
Correct answer: b
Review Question Answers
Chapter 3 | Fuel Gas Delivery
1. A customer calls to complain that his 40,000 Btu/hr propane hearth appliance is pe is
performing below normal. The outside temperature is 32° F (0° C). Which of the following best
explains the hearth appliance's performance?
a. In cold weather, propane moves more slowly from the storage tank to the appliance.
b. If the fuel level in the tank is low in cold weather, the vaporizing capacity of the tank may not
be equal to the Btu/hr capacity.
c. When the outside temperature reaches 32° F (0° C). propane freezes and vaporizing capacity
ends.
d. The "wetted surface of a storage tank is ineffective when the outside temperature reaches 32"
F (0° C).
Correct answer: b
2. What is the typical residential delivery pressure for a LP regulator?
a. 3-6" WC
b. 7-10 WC
c. 11-14" WC
d. 15-18" WC
Correct answer: c
Chapter 4 | Gas Piping Guidelines
1. Which of the following diagrams shows the correct configuration for a sediment trap
installation in a gas supply system?
Correct answer: b
コー
2. Which of the following is NOT acceptable electrical grounding and bonding for gas piping
according to the fuel gas codes?
a. Corrugated stainless-steel tubing (CSST) bonded to electrical service grounding system at
the point where the gas service enters the building
b. Rigid gas piping used as a grounding conductor
c. Pipe bonded through connection to appliances connected to grounding conductor of circuit
supplying the appliance.
d. 6 AWG copper wire used for CSST bonding
Correct answer: b
3. Which of the following is NOT a factor that can influence gas pipe sizing when using the
Longest Run Method?
a. Heat value of the gas
b. Number of 90 bends
c. Specific gravity
d. Pressure losses through sections of piping
Correct answer: d
4. Which of the following statements about leak detection is FALSE
a. Electronic sniffers are sensitive to combustible gases other than natural and LP gases.
b. Soapy water solutions may cause corrosion.
c. Leak detection procedures are only necessary if gas is smelled.
d. Fittings that are disturbed during installation and service should be leak tested.
Correct answer: c
5. An accessible, approved shutoff valve must be installed in the piping within a specified
proximity to each appliance to allow for:
a. foundation settling.
b. concealed pipe joints.
c. servicing, removal, and replacement.
d. reduction in gas pressure.
Correct answer: c
Chapter 5 | Hearth Appliance Categories
1. Which of the following is true about the efficiency ratings provided by Annual Fuel Utilization
Efficiency
(AFUE) and Steady State Efficiency?
a. Although established by different government agencies, the two rating systems are identical.
b. Steady State Efficiency ratings are likely to be higher than AFUE ratings since they do not
include start up or cool down periods
c. AFUE and Steady State Efficiency ratings are required for decorative appliances.
d. AFUE and Steady State Efficiency ratings are required for heater rated appliances.
Correct answer: b
2. According to the ANSI standard, unvented room heaters, other than for bedrooms or
bathrooms, can
NOT have an input rating in excess of:
a. 10,000 Btu/hr
b. 20,000 Btu/hr
c. 40,000 Btu/hr
d. 60,000 Btu/hr
Correct answer: c
3. Which of the following is NOT a function of the automatic gas control valve?
a. Maintaining a steady and even flow of gas.
b. Mixing the proper air and fuel mixture.
c. Shutting off gas flow in the event of loss of flame.
d. Providing both a manual and electronic control of
gas flow. Correct answer: b
Chapter 6 | Principles of Gas Appliance Venting
1. How much dilution air is required when burning 100 cubic feet of natural gas in a direct vent
appliance?
a. 250 cubic feet
b. 800 cubic feet
c. 2,600 cubic feet
d. Direct Vent appliances do not require dilution air
Correct answer: d
2. Natural draft appliances that normally operate at vent temperatures that avoids excessive
condensate problems in the vent are classified as:
a. Category 1
b. Category 2
c. Category 3
d. Category 4
Correct answer a
Chapter 7 | Venting Classifications
1. How tall must a gas vent that terminates closer than 8 feet from a vertical wall?
a.2 feet
b. 3 feet
c. 8 feet
d. 10 feet.
Correct answer: с
2. B Vent pipe is tested to:
480 degrees
b. 1000 degrees
c. 1700 degrees
d. 2100 degrees
Correct answer: a
3. Which vent type allows dilution air to enter the system?
B Vent b. Direct Vent
c. Masonry
d. Factory-Built UL 103 HT Chimneys
Correct answer: a
4. Which of the following is not an acceptable chimney
liner for gas hearth appliances? a. Single wall galvanized pipe
b. Aluminum flex pipe
c. Stainless-steel rigid pipe
d. Type B vent
Correct answer: a
Chapter 8 | Ventilation, Combustion Air & Building Thermal Efficiency
1. A 60,000 Btu gas log set is to be installed in a space that is not of sufficient volume to provide
adequate combustion air. Additional combustion air will be supplied from an adjacent room
using two permanent openings in the wall. The fuel gas codes state that these openings must
meet the following requirements:
Each opening must provide opening per 1,000 Btu input and must not than 100 square inches at
least 1 square inch of the less in total area.
The minimum dimension of air openings shall not be less than 3 inches.
What size is required for each ach opening to satisfy the
requirements of this installation!
a. 20" x 3"
b. 4 ^ prime prime *25^ prime prime
= 30 ^ prime prime *2^ prime prime
Correct answer: b
2. A conventional vent gas fireplace is to be installed in a room that is 20' * 15' with an 8' ceiling.
The house has a known 0.35 air change per hour (ACH). Use the Known Air Infiltration Rate
(KAIR) formula below to determine which of the following is the highest possible gas fireplace
input rating for this toom, without providing additional combustion air.
a. 24.000 Btu/hr
b. 35,000 Btu/hr
I other
c. 40,000 Btu/hr
1000Bm / h * r
d. 60,000 Btu/hr
Correct answer: c
3. What information is not needed for determining combustion air requirements for a room when
using the Standard Method nd in the fuel gas codes?
]
Ceiling height
b. Tightness of building construction
c. Use of the room
d. Input rating of all appliances in the room
Correct answer: b
4. The IRC requires a blower door tested to be conducted at
Minus 50 inches of water column
1. Minus 50 psi
c. Minus 50 Pascals
d. Minus 50 ACH
Correct answer: с
Chapter 9 | Hearth System Installation Guidelines
1. What is the maximum wall temperature during safety testing for a fireplace when the ambient
room temperature is 65" F
90 F
b. 117 F
155 F
d. 182 F
Correct answer: d
2. Ducted heat management systems.
a may only be used in commercial installation.
b. must have a safety screen in front of the unit.
c. may allow the installation of a television above the fireplace.
d. must have a sprinkler system installed above the unit.
Correct answer: c
Chapter 10
Conventional Vent Appliance Installation Guidelines
1. According to the National Fuel Gas Code (NFPA 54), which of the following situations does
not require a provision for outside ait for conventionally vented
appliances? a. Unusually tight construction, confined space.
b. Unusually tight construction, unconfined space
c. Normal construction, confined space
d. Normal construction, unconfined space
Correct answer: d
2. Which of the following is true about the damper opening requirement for vented gas log sets?
a. The damper stop maintains a minimum opening whether the gas log set is being operated or
not.
b. The gas log set should not be operated with the damper opening greater than the opening
size that
the damper stop allows, c. The damper must be present and operable.
d. Dampers with adjustable positions do not require a damper stop.
Correct answer: a
3. What type of venting systems used with factory built, conventionally vented gas fireplaces?
a. Direct Vent
b. Masonry
c. Flexible stainless-steel
d. B Vent
Correct answer: d
4. B vent pipe that extends more than above the minimum termination heights in the
manufacturer's chart must be protected in an unventilated enclosure or chase insulated to at
least a R8.
a. 2 feet
b. 3 feet
5 feet
d. 8 feet
Correct answer: c
Chapter 11 | Direct Vent Appliance Installation Guidelines
1. Which of the following is true about gas appliance venting system clearances?
a. Direct vent clearances may be different for horizontal
and vertical portions of the same venting system. b. Gas appliance vent clearances are
established by the fuel gas codes.
c. Clearances for a solid fuel factory-built chimney are reduced when the chimney is used to
vent gas hearth appliances.
d. Fiberglass insulation reduces clearances for gas
appliance venting systems.
Correct answer: a
2. A direct vent fireplace is to be vented on an outside wall of a house in the United States. The
termination will be under a deck. The front of the deck has lattice work from the deck to the
ground, and the two sides are open. The centerline of the 8"OD vent termination is 24" above
grade. According to the figure below, which of the following is the minimum height above grade
for the bottom of the deck!
4. 36"
b. 40"
44"
d. This fireplace cannot be installed in this location.
Correct answer: b
Termination cap
Air supply siet
Restricted arva Dermination prohibited)
3. A direct vent fireplace is to be vented on an outside wall of a house in the United States with
the termination located between an outside corner of the home and a window that can be
opened. A round horizontal termination with an 8" outside diameter will be used. The edge of the
window is 20" from the outside corner. Using the manufacturer's instructions below, what is the
maximum Beu fireplace that can be installed?
a. 8,000 Btu fireplace b. 20,000 Btu fireplace
50,000 Btu fireplace
d. It is not possible to install a fireplace from this manufacturer in this location.
Correct answer, a
4. What is the purpose of a direct vent restrictor plate?
a. Decrease heat output b. Decrease effects of draft
c. Make flame brighter
d. Keep birds out of the vent
Correct answer: b
Chapter 12 | Direct Vent Power Vent
1. Which of the following statements is correct regarding the safety of a power vented
(mechanical draft direct vent) appliance in the event of a power outage!
a. It is necessary to have a generator tied into the system.
b. Without the fan running, the system will overheat and a safety switch will shut it down.
c. The fan is interlocked with the control valve, so the gas will shut off when the fan stops.
d. If the vent includes at least 8 feet of vertical pipe, the appliance will continue operation with
natural draft Correct answer: с
2. What is most likely to occur if the venting in a positive pressure power vent system is
<u>not<u> properly sealed!
a. Air will be drawn into the vent gaps.
b. Combustion byproducts will be pushed out. c. Backdrafts will be created, shutting down the
appliance.
d. The heating capacity of the appliance will be decreased.
Correct answer: b
Chapter 13 | Unvented Appliance Installation Guidelines
1. You are installing a solid fuel factory-built fireplace that is approved for a specific set of
unvented gas logs. Local codes permit unvented appliances and you plan to place the approved
unvented logs in the fireplace. The
fireplace chimney: a. does not have to be installed.
b. may be terminated in the attic.
c. must extend to the outdoors and be in compliance with height requirements.
d. must be equipped with a termination cap designed for unvented logs.
Correct answer: c
2. Which of the following statements is true about installing an unvented gas log set in a factorybuilt solid fuel fireplace!
The chimney does not have to be present.
b. The damper must be removed or blocked open.
c. The fireplace must be listed for use with unvented hearth appliances.
d. The unvented gas log ser can be installed in any factory-built fireplace if the fireplace is not
located in a bedroom or bathroom.
Correct answer: c
3. According to the ANSI standard, unvented room heaters, other than for bedrooms or
bathrooms, must have an input rating equal to or less than:
10,000 Btu
b. 20,000 Btu
40,000 Btu
d. 60,000 Btu
Correct answer: c
Chapter 14 | Outdoor Gas Appliances
1. Enclosures for propane cylinders used with outdoor appliances must
be sealed air tight to prevent leakage.
b. be in the same space as the burner compartment follow the enclosure requirements outlined
in NFPA 211
d. follow the enclosure requirements specified in the
ANSI Z21.97
Correct answer, d
2. An appliance is considered to be outside if it hast
Walls on four sides with an overhead cover b. Walls on four sides and no overhead cover
Ventilated walls on four sides and an overhead cover
d. Ventilated walls on four sides and a ventilated cover
Correct answer: b
Chapter 15 | Thermostats, Wall Switches, Remote Controls
1. A homeowner has an existing gas fireplace that was installed by a general contractor. She
currently has a wall switch and would like to replace it with a remote control that has as many
features as possible. According to the owner's manual instructions below, what type of remote
control (if any) may she use?
a. A battery-operated on/off thermostat remote control with a battery operated receiver
b. A battery-operated on/off remote control with a battery operated receiver
c. A battery-operated remote on/off thermostat control with a110V receiver
d. This fireplace may not be operated with a remote
control
Correct answer: b
2. You are working with a millivolt gas control system that includes a thermopile and
thermocouple. Which of the Following may result from exceeding the manufacturer's length
requirements on thermostat wire for this system? a. Pilot will shut off
b. Main burner will not turn on
c. Excessive heat buildup in wire
d. Valve will not close
Correct answer: b
3. Which of the following is a proper procedure for installing a gas hearth appliance thermostat
a. The thermostat wire should be 22 gauge speaker wire for a millivolt thermostat.
b. A UL listed thermostat should be added to a vented gas fireplace listed to ANSI Z21.50
(Vented Fireplaces).
c. The thermostat should be located on an interior wall.
d. The thermostat should be located within 3 feet of the appliance it control Correct answer: c
4. Under which ANSI standard must a gas appliance be listed to allow for the use of a
thermostat
ANSI Z21.84-Manually Lighted, Natural Gas Decorative Gas Appliances for Installation in SolidFuel Burning Appliances
b . ANSI Z21.50-Vented Gas Fireplaces
C. ANSI Z21.60-Decorative Gas Appliances for Installation in Solid-Fuel Fireplaces
d. ANSI Z21.88-Vented Gas Fireplace Heaters Correct answer: d
Chapter 16 | Installation: Putting the Appliance in Operation
1. Which of the following procedures is NOT recommended for purging small amounts of air
from a gas line?
a. Disconnect the flex line
b. Loosen inward pressure tap
c. Remove the pilot adjustment screw
d. Hold the valve open in the pilot position
Cortect answer: a
This appliance complies with National Safety and is tested and listed to ANSI 221.50-2003 as
vented gas freeplaces
Installation and service must be performed by a locally certified gas service agent cesed
plumber, or the gas supplier Installation must conform to local codes. Check local codes prior to
installation
In the absence of local codes, Installation must confarm with cument National Fuel Cias Code
ANGI Z223.1
Installer Leave this manual with the appliance Consumer: Retain the manual for future reference
2. A trained fireplace technician should check for leaks by
using a(n): multimeter.
b. match.
electronic sniffer.
d. carbon monoxide (CO) detector.
Correct answer: c
3. Which of the following indicates spillage from a gas appliance?
a. The appliance will not turn on. b. The appliance will not shut off.
c. A match flame is drawn into the front of the appliance
d. A match flame is blown away from the draft hood.
Cortect answer: d
Chapter 17 Manual Gas Control Valves
1. What is the function of the electromagnetic power unit
(EPU) on a control valve!
a. Provide electrical power for the valve.
b. Close the valve when the pilot flame is lost.
Extract magnetic particles from the gas line.
d. Receive a signal from remote control.
Correct answer: h
2. What is the average millivolt output of a thermocouple under no load
a. 15-20 millivolts
h. 25-30 millivolts
c. 100-250 millivolts
d. 250-750 millivults
Correct answer: b
3. When a continuous (standing) pilot is being lit, the operator must depress the control knob in
the pilot position for 30-60 seconds to allow enough time:
a to light the burner.
b. for the pressure regulator to stabilize gas pressure.
c. to generate sufficient millivoltage.
d. to evacuate unburned gas before the main burner
ignites.
Correct answer: c
Chapter 18 Automatic Millivolt Powered Gas
Control Valves
1. Which of the following is the automatic gas control valve component which controls whether
gas flows to the main burner in response to heat demand?
a. Valve operator
b. Automatic safety shutoff system
c. Pressure regulator
d. Manual valve
Correct answer: a
2. Which of the following components is used with an automatic gas control valve, but not with a
manual gas control valve?
a. Pilot safety shutoff system
b. Thermocouple
c. Pilot adjustment screw
d. Remote control
Correct answer: d
3. A millivolt valve has a thermocouple and a thermopile. Which of the following may result from
exceeding the manufacturer's length requirements on thermostat wire for this valve?
a. Pilot will shut off
b. Main burner will not turn on
c. Excessive heat buildup in wire
d. Valve will not close
Correct answer: b
Review Question Answers
Chapter 19 | Millivolt Standing Pilot Ignition Systems
1. What is the proper procedure for adjusting a pilot flame
a. Turn the adjustment scww clockwise to increase the pilot flame.
b. Remove the protective cap and unscrew the adjustment screw completely to adjust an active
pilot flame.
Adjust the pilot flame until it is a soft yellow flame.
d. Keep face, hands, and clothing out of a direct line with the pilot adjustment port.
Correct answer: d
2. Oxygen depletion sensors (ODS) shut off gas flow when oxygen levels are low by means of:
a narrow range of stable pilot flame operation.
b. an electronic module that senses oxygen levels below 18%.
can adjustable thermopile that can be set for the proper oxygen level.
d. the flammability limits of the fuel gas
Correct answer: a
3. It is important that the pilot flame engulf only the hot junction of a thermocouple/thermopile
because the:
lower portion is not heat protected.
b. hotter the upper portion and the cooler the lower portion, the greater millivoltage produced.
lower portion does not respond to heat.
d. pilot flame cannot adequately heat the entire thermocouple/thermopile.
Correct answer: h
Chapter 20 | Troubleshooting Millivolt System
1. Which of the following instruments is necessary to troubleshoot the thermopile/thermocouple
if the pilot light fails to stay lit?
a. Multimeter
b. Manometer
Magnehelic gauge
d. Electronic gas sniffer
Correct answer: a
2. To troubleshoot gas valves, a multimeter must be
capable of measuring: millivolts DC.
b. inches water column.
c. Btus per hour.
d. surface temperature.
Correct answer: a
184 Ges Reference Manual | 7th Edition
3. Which of the following is a possible cause for fluctuating flames on a gas appliance?
Improper log placement
b. Improper ember placement
c. Defective regulator d. Restricted venting
Correct answer: c
Chapter 21 |
Electronic Gas Control Systems
1. How do electronic ignition systems that normally operate with AC voltage ensure gas flow
shutoff in the
loss of the pilot or main burner flame?
a. Flame rectification
b. Thermocouple/thermopile
c. Pressure regulator sensing device
d. Oxygen depletion sensor (ODS)
Correct answer: a
2. In which part of an electronic ignition safety system is the alternating current (AC) converted
to direct current (DC)
a. Flame rod
h. Control module
c. Burner flame
d. Electromagnet
Correct answer c
3. Which of the following ignition systems does not require 110 VAC power?
a. Direct spark
b. Standing pilot
c. Hot surface
d. Hot wire
Correct answer: b
Chapter 22 | Troubleshooting Electronic Systems
1. Poor electrical grounding of the main burner on a direct spark or hot surface ignition system
can cause: a. severe electrical shock
b. small main burner flames.
c. the main burner to not stay lit.
d. damage to the control module.
Correct answer: c
2. An electronic ignition appliance is turning on and off unexpectedly when the flame is in the
right zone of the flame rod/sensor. A continuity check between the control module and burner
pan shows no problems. What action should be taken?
a. Increase gas presure using a pressure gauge.
b. Adjust the main burner air shutter.
c. Replace the gas control valve.
d. Replace the control module.
Correct answer. d
3. In a gas appliance controlled by an electronic valve, which of the following causes an
unexpected loss of flame to shut gas flow off completely?
a. An interruption of an electrical signal
b. A detected drop in gas pressure
c. A monitored temperature drop
d. Failure to meet room heat demand within a set time
period
Correct answer a
Chapter 24 Orifices
1. Which of the following statements is true about gas orifices?
a. Burrs in orifices causing noise can be removed by using a drill bit.
b. Larger numbers mean larger openings on pilot orifices.
c. Converting an appliance from propane to natural ga will require a smaller orifice.
d. A significant increase in gas pressure requires a larger orifice to maintain the same input
rating.
Correct answer: b
4. Poor electrical grounding of the main burner on a direct spark or hot surface ignition system
can cause
2. Which of the following main burner flame problems would <u>not<u> be caused by orifice
blockage?
severe electrical shock.
b. small main burner flames..
the main burner to not stay lit.
d. damage to the control module.
Correct answer: c
Chapter 23 | Safety & Operational Switches
1. Which of the following devices that prevents appliance operation is <u>not<u> dependent on
sensing heat?
a. Limit switch
b. Thermocouple
c. Lockout switch
d. Vent safety shutoff
Correct answer c
2. Which switch in a gas hearth appliance responds to excessively high temperatures by
shutting off the
appliance? a. Lockout switch
b. Dip switch
c. Bypass switch
d. Limit switch
Correct answer d
3. A customer's fireplace blower stops working. Which of the following is NOT part of the
procedure to safely
check the blower snap-switch? a. Disconnect the power to the circuit.
b. Set the meter to AC volts.
c. Disconnect one lead on the snap switch,
d. Apply heat to the snap switch.
Correct answer: b
a. Small flames
b. Fluctuating flames
c. Blowing flames
d. Low heat output
Correct answer: c
3. What will happen to the gas flow if gas pressure and orifice size are maintained as constants
and the fuel gas is changed to a fuel gas with lower specific gravity!
a. The volume of gas flow will increase.
h. The volume of gas flow will decrease.
c. The volume of gas flow will remain constant.
d. No gas will flow.
Correct answer: a
Chapter 25 | Main Gas Burners
1. Because air is constantly moving toward the pilot and main burner when they are burning, it is
necessary to a. conduct annual service to clean primary air openings
b. increase the size of the primary air openings.
c. increase the gas flow.
d. do nothing since the flame burns off all dust.
Correct answer: a
2. Which of the following is not a possible symptom of a
cracked burner?
a. Sooting
b. Hard, lifting flames
c. Lazy, floating flames
d. Flashback
Correct answer: b
Chapter 26 Troubleshooting Main Burner Performance Problems
1. Which of the following main burner flame problems is caused by lack of combustion air and is
usually accompanied by the odor of aldehydes?
a. Floating flames
b. Lifting flames
Fluctuating flames
d. Wavering flames
Correct answer: a
2. Which of the following statements is true about gas orifices?
a. Burrs in orifices causing noise can be removed by using a drill bit.
b. Larger numbers mean larger openings on pilot orifices
c. Converting an appliance from propane to natural gas will require a smaller orifice.
d. A significant increase in gas pressure requires a larger orifice to maintain the same input
rating.
Correct answer: b
3. Which of the following can result from incorrect log
placement?
a. Log breakage from excessive heat
b. Carbon monoxide production
c. Blue flame
d. Burner noise
Correct answer: b
Chapter 27 | Venting & Ventilation Problems
1. A stronger draft in a natural draft venting system will
result from an increase in:
a. inlet gas pressure.
b. vent system resistance.
c. building envelope temperature.
d. vent gas temperature.
Correct answer: d
2. Which of the following could be the cause of small, blue, active flames in a vertically
terminated direct vent fireplace?
a. Undersized main burner orifice
b. Low gas pressure
c. Resistance to exhaust flow due to too many elbows
d. Excessive vent draft
Correct answer: d
3. After burning for 30 minutes, a new direct vent stove is displaying an inconsistent flame that is
rising and falling. To troubleshoot, you remove the glass front, and the unit burns properly. What
should you do next to diagnose the problem?
a. Check the log placement for flame impingement.
b. Check for insufficient inlet gas pressure.
c. Check the venting for leaks or obstructions.
d. Check the air shutter for proper adjustment.
Correct answer: c
Chapter 28 | Annual Service
1. Because air is constantly moving toward the pilot and main burner when they are burning, it is
necessary to:
a. conduct annual service to clean primary air openings.
b. increase the size of the primary air openings.
increase the gas flow
d. do nothing since the flame burns off all dust.
Correct answer: a
2. Which of the following is the best precaution for avoiding electrical shock during installation or
service work
a. Keeping the current on only when working with a 24. VAC transformer.
h. Switching off the circuit breaker that serves the appliance.
Turning off the wall switch that serves the appliance. d. Setting the thermostat above the room
temperature. Correct answer: b
Chapter 29 | Repair & Fuel Conversion Service
1. Which of the following is NOT a component that must
be altered in a fuel conversion?
a. Thermocouple/thermopile
b. Pressure regulator
c. Orifice
d. Primary air shutter
Correct answer: a
2. Which of the following does NOT require an adjustment procedure in a fuel gas conversion?
a. Air
b. Fud
c. Heat
d. Pressure
Correct answer: c