39HQM Central Station Air Handling Units
Installation, Operation and Maintenance
Instructions
Page 1 of 20
Table of Contents
1 – SAFETY CONSIDERATIONS .................................................................................................................................................. 3
1.1. General ............................................................................................................................................................................... 3
1.2 Applications .......................................................................................................................................................................... 3
1.3 Instruction types ................................................................................................................................................................... 3
1.4 Disposal of parts/materials ................................................................................................................................................... 4
2 – TRANSPORT AND LIFTING INSTRUCTIONS ........................................................................................................................ 4
2.1. General ................................................................................................................................................................................ 4
2.2 Transport and Storage.......................................................................................................................................................... 4
2.3 Roof edge protection during transport (outside installation) ................................................................................................. 5
2.4 Offloading and Hoisting ........................................................................................................................................................ 5
2.5 Horizontal transport .............................................................................................................................................................. 5
3 – AHU STORAGE REQUIREMENTS ......................................................................................................................................... 6
4 – STARTUP INSTRUCTIONS ..................................................................................................................................................... 7
4.1 Casing .................................................................................................................................................................................. 7
4.2 Dampers ............................................................................................................................................................................... 8
4.3 Air Filters .............................................................................................................................................................................. 8
4.4 Electric Heaters .................................................................................................................................................................... 8
4.5 Drain Connection.................................................................................................................................................................. 8
4.6 Cooling Coil .......................................................................................................................................................................... 9
4.7 Plate Heat Exchanger........................................................................................................................................................... 9
4.8 Heat Recovery Wheel......................................................................................................................................................... 10
4.9 Fan and Motor .................................................................................................................................................................... 10
4.10 Drive Package .................................................................................................................................................................. 11
5 – MAINTANANCE AND OPERATING INSTRUCTIONS .......................................................................................................... 12
5.1 General ............................................................................................................................................................................... 12
5.2 Casing Panels .................................................................................................................................................................... 12
5.3 Doors and Access Covers .................................................................................................................................................. 12
5.4 Flexible Connections .......................................................................................................................................................... 12
5.5 Earthing .............................................................................................................................................................................. 12
5.6 Dampers ............................................................................................................................................................................. 12
5.7 Outside Air Intake ............................................................................................................................................................... 12
5.8 Filters.................................................................................................................................................................................. 12
5.9 Electric Heaters .................................................................................................................................................................. 12
5.10 Cooling Coil ...................................................................................................................................................................... 12
5.11 Heat Recovery Wheel....................................................................................................................................................... 12
5.12 Plate Heat Exchanger....................................................................................................................................................... 13
5.13 Fan ................................................................................................................................................................................... 13
5.14 Sound Attenuator ............................................................................................................................................................. 13
6 – 39HQM WITH STARTER PANEL .......................................................................................................................................... 14
7 – HYGENIC AIR HANDLING UNITS GUIDELINES .................................................................................................................. 15
8 – MAINTENANCE CHECKLIST ................................................................................................................................................ 16
9 – HYGENIC AHU MAINTENANCE CHECKLIST ...................................................................................................................... 17
10 – AHU TROUBLESHOOTING GUIDE ................................................................................................................................... 18
11 – MANDATORY START-UP CHECK LIST AND RECORD .................................................................................................... 19
Page 2 of 20
1 – SAFETY CONSIDERATIONS
Earthing
1.1 – General
The 39HQM air handling units (AHUs) has been
manufactured in Carrier factory in the Kingdom of
Saudi Arabia, under the guidelines and policies of
Global Carrier Corporation. In order to guarantee safe
operation and use of the unit, please carefully read and
observe the instructions in this document and pay
special attention to the warnings that apply to this unit.
Any modifications in the design and/or installation of
the AHU that are carried out without discussion with
Carrier Corporation and without advance written
agreement will result in the loss of the right to any
warranty claims and any claim for injury to personnel
as a result of these modifications.
Maintenance procedures may only be carried out by
qualified personnel.
1.2 – Applications
The AHU is designed for the movement and
conditioning of air, unless otherwise agreed during the
design stage.
1.3 - Instruction Types
The following warning labels and labels with text are
used.
Lifting point
This label indicates where the AHU must be earthed
and is on one of the support beams beneath the casing
in the fan section.
- The electrical components in the AHU must be
earthed, except for components with double insulation
and/or components with a supply voltage below 50 V.
- The electrical components must be installed in
accordance with national and local regulations.
Rotating parts
This label indicates that there are rotating parts behind
this access cover, door or panel which may cause
injury. The components that include rotating parts are
the fan and heat recovery wheel. If there are special
customer-specific components behind doors, access
covers or panels that include rotating parts and pose a
potential risk, this is also indicated by this label.
Hot surfaces
This label shows where the AHU must be lifted and is
positioned on the support beam.
Forklift Handling
All sections are produced with a base frame and
optionally can be placed on a wooden block for
positioning with a forklift.
This label indicates that there are components behind
this access cover, door or panel that can cause serious
burns when touched.
The components that may have hot surfaces are the
steam humidifier, steam heater and the electric heater.
If there are special customer-specific components
behind doors, access covers or panels that have hot
surfaces and pose a potential risk, this is also indicated
by this label.
Electrical voltage
- Place the forklift under the center of gravity of the
section for equilibrium and maximum safety.
- Confirm that the forklift has adequate lifting capacity
for each section to be moved.
Page 3 of 20
This label indicates that there are electrical
components behind this access cover, door or panel
that may be dangerous for the user/installer. Only
personnel qualified in accordance with NEN 3140 is
permitted to carry out work on these components. The
label is attached to the access cover for the electric
heater control box.
Removal of transport brackets
This label is located at the bottom of the fan section. It
indicates that the transport brackets must be removed
during commissioning before the fan is started up.
Central data
Remove Wooden blocks underneath fan motor base, if
any.
Unfasten all screws and remove
the shipping clamps
Sample of rating plate, above, contains the data for the
AHU, such as Project Name, Section number, power
supply, air flow etc. the Rating Plate is normally
located on the access cover or the door of the fan
assembly.
Opening the fan door
Before opening doors, switch off and deenergize the fan, and ensure that it has
stopped rotating. (Minimum of 2 minutes)
Before starting the unit removes
the 4 fan shipping clamps.
Untighten spring isolator bolt
Partially un-tight (loose) the nut of spring isolator as
shown below. Move up the isolator bolt min 25 mm,
using Allen or vise grip, this will disconnect the spring
bolt from bottom Spring Plate, Tighten again the nut for
all spring isolators so that the Fan Motor Base is
secured to the top spring isolator plate. Label is
located at the inner skin of the access door of the fan
section.
Partially untie the nut before
applying the Allen Key.
Loosen the spring bolts (min 25mm)
with the help of Allen Key, till you hear
a click sound indicating spring bolt
being disconnected from bottom
spring plate.
This label is positioned on the outside of the door or
access cover of the fan assembly. This label warns
that the fan must have been switched off and deenergized for a minimum of two minutes before the
door or access cover is opened.
Caution: All doors and access covers must be closed
before starting up the AHU.
1.4 - Disposal of Parts/Materials
- The packaging material must be disposed of in a
responsible manner and in accordance with local
regulations.
- Components that are replaced must be disposed of
as described above.
2 – TRANSPORT AND LIFTING
INSTRUCTIONS
2.1 - General
Transport and lifting of the AHU must always be in
accordance with the instructions below. If these
instructions are not observed, irreparable damage may
occur to the unit, and people in the immediate vicinity
of the unit are also endangered. Carrier does not
accept any responsibility if these instructions are not
observed. Transport and lifting must be carried out by
qualified personnel. Lifting must be carried out in
accordance with local regulations and with the help of
certified lifting aids.
Top Spring Plate
25 mm minimum
Bottom Spring Plate
2.2 - Transport and Storage
Lifting of the AHU is only permitted under the
designated lifting points. This applies to transport as
well as storage.
Tighten the nut again to secure
the fan and motor base frame.
Page 4 of 20
2.3 - Roof Edge Protection During Transport
(Outside Installation)
Evenly positioned spacer bars should be used
between the lifting cables to prevent damage to the top
of the unit and ensure that no excess pressure is
applied to the AHU panels. For hoisting please ensure
that the weight is evenly distributed.
Bed Truck
Roof edge transport protection
During transport by truck the units are attached to the
loading surface with tie ropes, pulled across the unit
towards the side edges of the truck.
On external units, to protect the roof edge from
distortion by the tie ropes protection plates are added.
2.4 – Offloading and Hoisting
Depending on the dimensions of the AHU and the
situation on site, the AHUs are supplied in previously
agreed transport sections.
Before proceeding with the transport and installation of
the casing sections, always consult the applicable
dimensional drawing which shows the dimensions and
weights of the sections, as well as the installation
sequence.
The weight is given on each transport section. Each
transport section is equipped with a sub frame with
four lifting points. These points are marked by the label
shown below.
For offloading as well as hoisting lifting cables can be
attached
1) Under the wooden skid OR
For hoisting please ensure that the
weight is evenly distributed.
Ensure that spacer is used in the
hoisting properly so no pressure is
applied on AHU casing.
2) To the lifting bars. (Lifting bars are not
supplied by factory )
Page 5 of 20
2.5 - Horizontal Transport
For horizontal movement pallet lifters or transport skids
can be placed under the installation frame or under the
lifting bars. It is important that these support the lifting
points. At no time should the cross beams at the ends
of the unit sections be used for jacking or tracking the
AHU.
For horizontal transport always provide support under
the lifting points.
- The use of bars / tubes as rollers can result in damage to
the installation frame.
- Roller should be adequate to support the weight of the
AHU section
- The roller used for AHU horizontal transport MUST BE
FREE ROLLING.
- The rollers are not supplied by factory.
3 – AHU STORAGE REQUIREMENTS
Store Indoor before Installation
3.2 – Long Term Storage
Storage period that took longer than 6 months inside
the controlled environment, as explained above in
Normal storage, less than 6 months; still require
serious and proper preservation actions during the
storage period
3.1 – Short Term Storage
To properly store the AHU, it is critical to meeting the
storage requirements as per the following;
3.2.1 Belts to be removed and kept safe with proper
tag of the AHU in conditioned space, belts shipped
loose, as standard in production of 39HQM and
packed in plastic bag placed inside fan section.
3.1.1 Indoor storage weather: < 70% RH, < 40º C, all
AHUs sections are clearly label with sticker mentioning
“STORE INDOOR”
3.2.2 Filters to be removed and stored in a proper
packed & conditioned space.
3.1.2 Well ventilated store room precaution to prevent
internal condensation that can lead to rust.
3.2.3 Every 3 months check fan bearing to see if relubricate is required
3.1.3 Clean and non-corrosive environment.
3.2.4 Every 3 months unload the bearing by turning the
fan wheel by hand. This operation prevents bearing
corrosion by redistributing the bearing grease.
3.1.4 Storage platform to be smooth with minimum
vibration and leveled.
3.1.5 Ensure properly packed or cover the AHU,
ensure the openings of the AHUs like the damper, fan
and coil opening are closed so that no dust, no
external material or animal allow to enter the AHU.
After long term storage, grease should be purged from
the bearing and fresh grease injected prior to start-up.
3.2.5 Motors should be stored in a clean, dry
environment protected from moisture.
3.2.6 Periodically check of the AHU packing to ensure
no sand/dust accumulation.
Page 6 of 20
4 – STARTUP INSTRUCTIONS
4.1 – Casing
A4 Sheet is attached to the unit for the unit data such
as project name, section number etc. This usually
located on the access cover or door of the fan
compartment.
4.1.1 Casing Panels
Check the AHU panels for any damage. Any dirt or
stains must be removed from the surface to prevent
possible long-term damage. Building debris left on the
roof must be removed. Dirt can be removed with water
and a mild household soap solution. Damage can be
repaired by thoroughly cleaning the affected surface,
then treat and paint as necessary. If applicable check
the sealing joints and repair if required.
Before the units are placed against or on top of each
other, the sealing tape supplied must be attached
between the casing sections.
Place the casing sections as close as possible
together before assembly. Pull the casing sections
towards each other by placing the lifting bars first in
one and then in the other casing section. Then pull
both parts towards each other using pull ropes.
The casing sections are connected with the frames
and fixing elements supplied. If the AHU is installed
outside, the roof connecting plate provided must be
installed on the roof and sealed.
4.1.2 - Doors and Access Covers
Check the operation of door handles, locks and
movement of the hinges. For outside installation of the
AHU check the storm cord.
Doors and access covers must always be
closed before starting the unit.
4.1.3 - Flexible Connections
Check that all flexible connections are attached to the
AHU. If necessary, tighten loose screws.
4.1.4 - Earthing
Ensure that the AHU has been earthed correctly and in
accordance with local regulations. A label on the
support frame indicates where the unit should be
earthed.
4.1.5.1 - Unit Joining With Half Mullion
(For units up to 16 widths)
4.1.5 - AHU Installation and Connection
The floor in the room where the AHU is installed must
be level and flat to prevent connection problems.
Use the pre-mounted corners for the final positioning of
the sections and secure the corners with a bolt. The
sections must be fully aligned.
In case of multi section unit It is highly recommended
to install common (single channel base through the
AHU) base channel underneath the AHU. Rubber
pads/ isolators will be installed underneath this single
channel base.
Page 7 of 20
Remove the first two corners and mount the GI
connection strip to the base. Remove the next two
corners and mount the connection strip against the
side wall. Repeat this for the other AHU corners.
4.1.5.2 - Unit Joining Corner Posts With
Coupling Profile
Ensure Coupling profile will be using for units for
sections that end with corner posts.
Ensure that the sealing tape supplied is fixed to one of
the two sections, before moving the sections against
each other.
Link the sections by connecting the pre-mounted
corner posts with bolts and nuts (M6).
If there are more than two sections, repeat the
procedure above. For an outdoor installation all
external joints should be sealed.
4.2 - Dampers
- Check if the actuator motor is installed in accordance
with the supplier’s instructions.
- Check if the correct angle has been set.
- Check if the dampers close properly.
- Check if the damper can open to the required angle.
- Check operation after the power has been restored
following a power cut. Some dampers must be open,
others must be closed.
4.3 – Air Filters
- Check if the correct filters have been installed.
- Check if the filters have been installed correctly.
- Absolute filters are supplied separately, to prevent
contamination during transport and start-up. Insert the
absolute filters only after the unit has been cleaned.
- Set pressure switches or filter indicators, if used.
- Close the inspection door.
Filter row can be
completely pulled out
in one move
4.4 – Electric Heaters
- Ensure that the heater has been connected in
accordance with the instructions of the supplier. The
heater wiring diagram is located on the inside of the
connection module.
- Check the heater current. Check if the safety devices
shown in the wiring diagram have been installed.
- Check if the heater has been earthed in accordance
with local instructions.
- The electric heater will be switched off if there is no
air flow rate across the heater exists, air flow switch
high pressure side should be connected to
atmospheric pressure in draw through arrangement
and reverse in-case of blow through arrangement.
- Ensure air flow switch is working.
- Ensure that no objects have been left in the heater
section.
- The following warning labels are attached to the
panel: electrical voltage and hot surface.
4.5 – Drain Connection
When calculating trap depth on draw-thru or blow-thru
applications, remember that it is not the total static
pressure but the upstream or downstream static
resistance that is trapped against.
When calculating the trap depth for a cooling coil
condensate pan on the draw-thru side, trap against the
coil pressure drop in that coil section and any other
pressure drops upstream of it (Negative Static
Pressure).
4.3 - Air Filters
Page 8 of 20
List of SCH40 steel pipes used in 39HQM standard
water coil connection. The connection size are as
reported in AHU coil’s report, the actual ID and OD
SCH40 as references, a guide to select other
connection accessories as for example the flanges,
reducers etc.
NSP = Negative Static Pressure
(in Pa)
L = Overall trap height
A = (NSP/250*25.4) + 50 (mm)
B = NSP
L = A + B + Pipe diameter
Condensate Drain, Draw-Thru Trapping
To determine the trap dimensions for blow-thru units,
find the coils maximum positive pressure and add 1/2
inch. This figure is normally the fan total static
pressure.
TSP = Total Static Pressure
(in Pa)
A = 50 mm (minimum)
B = (TSP/250*25.4) + 50 (mm)
L = A + B + Pipe diameter
Nominal Dia (in)
1 1/2
2
2 1/2
3
3 1/2
4
Actual I D (mm)
40.9
52.5
62.7
77.9
90.1
102.3
Actual OD (in)
48.3
60.3
73.0
88.9
101.6
114.3
Threaded flanges with SAMCO part number that are
readily available in market and used with the pipe
connection, the exception is for the flange size 2 ½”
Condensate Drain, Blow-Thru Trapping
- Check the connections in accordance with the
dimensional drawing.
- Control the connections for leaks.
- Check U- trap dimension according to above details.
- Insure no damage in fins. Correctly straighten the fins
- After several days of cooling operation check the
condensate drain and operation of the U trap, if
necessary clean it.
SAMCO Part Number
PIPE-FLANGE-1.5
PIPE-FLANGE-2.0
PIPE-FLANGE-2.5
PIPE-FLANGE-3.0
PIPE-FLANGE-4.0
Descriptions
Pipe flange 1.5 inches
Pipe flange 2.0 inches
Pipe flange 2.5 inches
Pipe flange 3.0 inches
Pipe flange 4.0 inches
For SCH40 pipe 2 ½” diameter, the readily available
threaded flange in the market cannot be used to
connect with SCH40 coil pipe 2 ½”. Blind Flange type
is to be used and to be machined to match the thread
with the SCH40 2 ½” coil’s pipe.
4.6 – Cooling Coil
All steel pipe connections that are used in 39HQM
standard water coil connection are selected from
Schedule 40 (SCH40) black steel type and the thread
is machined to BST 11 TPI (Taper 1:16). The size of
the SCH40 steel pipe connection for the coil is printed
as in per AHU selection report.
4.7 - Plate Heat Exchanger
Used if dampers are installed.
- Check if the actuator motor has been installed in
accordance with the instructions of the supplier.
- Check if the correct angle has been set.
- Check if the dampers close correctly.
- Check if the damper can open to the correct position.
- Check operation after the power has been restored
following a power cut. Some dampers must be open,
others must be closed.
- Insure no damage in fins. Correctly straighten the
fins.
Page 9 of 20
4.8 - Heat Recovery Wheel
- Check that the wheel is rotating in the correct
direction. This is indicated by an arrow on the casing.
- Check if the wheel seals are fitting correctly.
- Check if belt tension is correct.
- Check if the motor has been correctly connected.
- Check if the controller has been correctly connected
and set in accordance with the instructions of the
supplier if any.
- Check if the rotor speed has been set correctly.
- Heat wheel section is with access door as standard
for motor access.
data on the motor name plate. Set the motor protection
device to the nominal value.
The air flow may cause stationary parts to
move (even a fan that is switched off)
- The following warning label is attached to the panel:
rotating parts.
- If used check the pressure switch and set the correct
pressure.
While working on the fan the switch has to
be locked open.
- Check the operation of the main switch.
- The warning label on rotating parts, electrical voltage
and opening doors are attached to the door. The label
to remove the transport brackets is located on the floor
of the fan section.
4.9 – Fan and Motor
- Remove the transport brackets. This is indicated by a
label on the fan access door.
- Untighten spring isolator bolt refer to chapter 1.3.
- Check if the fan can move freely without obstructing
the frame, flexible connection or wiring.
- Insure power connection is star / Delta for motors
above 5.5 kW.
- Check and/or connect the motor in accordance with
local instructions and the data of the supplier.
- Check the direction of rotation of the impeller. The
direction is indicated on the fan casing by an arrow.
- Separately measure the current draw of the electric
motor for all phases. The current draw of all phases
must be approximately the same and agree with the
Page 10 of 20
Before opening doors, switch off and deenergize the fan, and ensure that it has
stopped rotating. (Minimum of 2 minutes)
4.10 – Drive Package
The data for the belt type, belt tension, number of
belts, size and type of pulley is indicated on a label
attached to access door of the unit. Belt is not factory
installed, supplied loose for site installation.
Span length
( mm )
Belt Tension
Force ( Kg )
Belt Deflection
( mm )
Using Laser guide device
Fan Pulley
Motor Pulley
Adjustable sheaves: To check the location of
adjustable sheave on shaft, make sure that the
centerlines of both sheaves are in line and parallel with
the bearing support channel. In case of adjustable
pitch drives, Carrier recommends that adjustable
sheaves should only be used for initial balancing and
be replaced with fixed pitch sheaves by the air
balancer prior to the final system air balance.
Belt
Unit Demo Sticker
4.10.1 – Alignment
Make sure that fan shafts and motor shafts are parallel
and level. The most common causes of misalignment
are nonparallel shafts and improperly located sheaves.
Where shafts are not parallel, belts on one side are
drawn tighter and pull more than their share of the
load. As a result, these belts wear out faster, requiring
the entire set to be replaced before it has given
maximum service. If misalignment is in the sheave,
belts enter and leave the grooves at an angle, causing
excessive belt and sheave wear.
4.10.1.1 Shaft Alignment
Shaft alignment can be checked by measuring the
distance between the shafts at 3 or more locations. If
the distances are equal, then the shafts are parallel.
4.10.1.2 Sheave Alignment
Fixed sheaves: To check the location of the fixed
sheaves on the shafts, a straightedge or laser guide
device is required.
Using Straightedge
Straightedge must make contact at 4 distinct
points along the outside perimeter of both pulleys
Page 11 of 20
Adjustable sheaves should not be used
with variable frequency drive
Do not exceed maximum fan speed with
adjustable sheave
5 – MAINTENANCE AND OPERATING
INSTRUCTIONS
5.1 - General
The AHU(s) require little maintenance. The smooth
inside and outside finish of the panels makes
maintenance very simple.
For dry sections: once a year thoroughly check the
inside and outside of the AHU casing. For
maintenance of wet sections (coolers and humidifiers)
please refer to the air handling section concerned.
5.2 – Casing Panels
5.2.1 - Inside Installation
a) Internal inspection of the casing of double-skin
panels and of all dry parts:
Remove contamination with water and a mild
household soap solution. Where damage of the paint
finish has occurred, if necessary remove rust and
touch up with good quality anti-corrosive primer and
paint. The outside air intake sections can show signs
of corrosion as they contain wet parts and are affected
by mist, rain and air pollutants.
b) Outside inspection of the coating:
If damage to the paint treatment has occurred, remove
the rust (if necessary), and touch up with good quality
anticorrosive primer and paint.
5.2.2 - Outside Installation
Check the sealed joints of AHUs installed outside and
if required seal again with a UV-resistant and paintable
kit. Treat damage as for inside installation.
5.3 - Doors and Access Covers
Check locks and hinges of all doors and access
covers.
5.4 - Flexible Connections
Check the flexible connections for damage.
5.5 - Earthing
Ensure that the unit is earthed and installed in the
correct manner.
5.6 - Dampers
Remove excess contamination by cleaning it with
compressed air. Check adjusting bolts and linkage and
if necessary tighten. Ensure that the damper blades
run free of the casing.
5.7 - Outside Air Intake
Especially the outside air intake is contaminated by
pollution taken in with the air. The maintenance interval
must be observed, as irreparable damage of the
panels might otherwise occur. Clean the outside air
intake well and repair damage as described in point
5.2.1.
Page 12 of 20
5.8 - Filters
The filters must be inspected once a month for excess
pollution, pressure loss, damage and seating of the
slide-in filters or built-in frames. With slide-in filters
ensure that the filters have been correctly positioned
and have been pushed well against each other from
below. When replacing built-in filters you must ensure
that the filter has been pushed well against the sealant
and that the clips have been correctly installed. Filters
must be replaced at the required intervals. The timing
of the replacement depends on the type of filter, quality
and the degree of contamination of the air. The
pressure loss across the contaminated filter can be
measured with a pressure differential gauge.
Maintenance instructions of special filters are available
on request.
5.9 - Electric Heaters
Check once a year for contamination, and if necessary
clean with compressed air. Check the connections in
the control box. Check the operation of the thermostat.
The following warning label is located on the panel:
electrical voltage and hot surface.
5.10 – Cooling Coil
Check once a year for contamination and if necessary
clean with compressed air against the direction of the
air flow or clean with a vacuum cleaner. Check for
leakage. Check the fins of the droplet eliminator after
the coil. Clean the siphon and check its operation.
Check the condensate pan for contamination and
clean if necessary.
5.11 - Heat Recovery Wheel
Check the rotor once a year for contamination, and if
necessary clean with compressed air. Check the rotor
speed and compare it with the design data.
Check the rotation of the rotor. Depending on the rotor
material the wheel can absorb moisture. When
stationary the wheel will become moist on one side
and thus heavier. The rotor speed can be set to
intermittent in the controller so that the wheel will rotate
“x” times per time unit.
The rotor bearings are lubricated for life and do not
require maintenance. The drive motor is accessible.
The belt is automatically tensioned by a spring-loaded
rocking base on which the motor is installed. New belts
expand a lot in the beginning. Check after two days if
the belt still has enough tension. After this check the
belt tension weekly during the first month and then
check it once a month.
For further operation and maintenance details on the
heat recovery wheel/controller refer to the
documentation provided by the supplier.
The following warning label is located on the panel:
rotating parts.
5.12 - Plate Heat Exchanger
Check the plate heat exchanger once a year for
contamination and if necessary clean with compressed
air against the direction of the air flow. If dampers are
used, follow the instructions in section 7.6
Check condensate pan for contamination and clean if
necessary.
5.13 - Fan
5.13.1 – General
wear and vibration, if it is too low this can result in belt
slippage and belt wear.
Sequence for installation of new belts:
- Ensure that the pulleys are correctly aligned. If
necessary re-align.
- Position all belts loosely on the pulleys; do not pull
tensioned belts over the pulleys.
- Tension the belts and check the tension with a Sonic
Tension Meter.
- Re-check the alignment.
If the fan speed changes or if a motor with different
power specifications and/or speed is installed, the
manufacturer must be informed. The supplier must recalculate the bearing load as well as the impeller load.
If this is not done, irreparable damage to the fan may
incur. The supplier does not accept any responsibility
for modifications that have not been approved. See
chapter 1.1.
- The warning pictograms indicating rotating parts,
electrical voltage and opening of doors are attached to
the door.
The air flow may cause stationary parts
to move (even a fan that is switched off)
While working on the fan the switch has
to be locked open.
The data for the belt type, belt tension, and number of
belts, size and type of pulley is indicated on a label
attached to the fan access door.
5.13.2 - Bearings
The bearings of the smaller fan types cannot be
lubricated. If the larger fans are of the re-lubricated
type, then they should be lubricated every six months.
For higher temperatures and increased contamination
the lubrication interval should be adjusted as required.
The standard lubricant is Shell Alvania R3. For higher
temperatures and a higher degree of humidity use a
lubricant recommended by the supplier.
The electric motors are equipped with roller bearings.
Depending on the motor size the bearings are
lubricated for life or are equipped with a grease nipple.
The lubrication interval and type of lubricant are as
above.
5.13.3 - Transmission
After starting up the unit, but also after replacing the
belts the belt tension has to be checked within one
week and then after two weeks and further tensioned if
required. After that check the belt tension and inspect
the condition of the belts every three months.
The Correct Belt Tension depends on:
- The belt type.
- Power to be transmitted.
- Belt velocity.
The belt tension is calculated for each transmission. If
the belt tension is too high this can result in bearing
Page 13 of 20
5.14 - Sound Attenuator
Under normal conditions the sound dampers are
maintenance-free. Nevertheless it is recommended to
check the attenuators once a year for possible damage
and loose fibers, in order to prevent further
contamination of the system.
Use the following formula to determine the percentage
of voltage imbalance.
6 – 39HQM WITH STARTER PANEL
6.1 - Electrical Connections:
Field Power Supply
- Before accessing the unit, verify safety procedures
are properly followed (LOCKOUT/TAGOUT).
- Technicians working on the electrical side of the AHU
must be trained in accordance to local national code
and other applicable national or international codes.
- Unit is factory wired for voltage shown on nameplate.
- Motor is factory wired, user is requested not to modify
the internal power or control wiring, doing so may lead
to Carrier warranty loss
- When installing units, provide a disconnect switch of
adequate size per NEC (National Electrical Code)
requirements,
- All field wiring must comply with NEC and local
requirements.
- Route field power lines to terminal box connections
as shown on unit wiring diagram and attached figure.
- Operating voltage to motor/s must be within voltage
range indicated on unit nameplate.
- On 3-phase units, voltages between phases must be
balanced within 2% and the current must be balanced
within 10%.
- Ensure connecting ground cable to factory ground
cable which is connected to equipment’s grounding.
- Every motor has standard internal thermal overload
Percentage of Voltage Imbalance
Max voltage de =100x variation from average voltage
average voltage
EXAMPLE: Supply voltage is 460-3-60.
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage = 455+464+455/3 = 457
Determine maximum deviation from average
(AB) 457 – 452 = 5 v
(BC) 464 – 457 = 7 v
(AC) 457 – 455 = 2 v
Maximum deviation is 7 v.
Determine percent voltage imbalance:
Percentage of Voltage Imbalance
= 100 x 7/ 457 =1.53 %
This amount of phase imbalance is satisfactory as it is
below the maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is
more than 2%, contact your local electric utility
company immediately.
Unit failure as a result of operation on improper line
Voltage or excessive phase imbalance
constitutes abuse and may cause damage to electrical
components.
Field Control Wiring
Route control cables or equivalent single leads
of no. 18 AWG (American Wire Gage) colored wire
from sub-base terminals through conduit in unit to
control connections as shown on unit’s label wiring
diagram.
Unit Start-Up
Switch on the power to the unit, check motor’s
operation and direction of rotation, if reversed
interchange two of the 3 power phases at terminal box
connections.
If unit is equipped with VFD, the initial settings
for the VFD are factory completed, other settings to be
completed at site as per load requirements.
Terminal Box
Page 14 of 20
7 - HYGIENIC AIR HANDLING UNITS
7.4 Commissioning / Acceptance
GUIDELINES:
Observe the following:
7.1 - Hygienic AHU Storage Requirements
Before switching on fans for the first time, make sure
that all parts in contact with the air are clean. Clean, if
required.
In addition to the 39HQM AHU storage requirement in
part 3, the following recommendation by VDI 6022
part1 should be taken care in the consideration for the
hygienic unit storage:
The packaging and protection of the components shall
only be removed immediately prior to assembly. Before
installation, the components shall be checked for
cleanliness, and shall be cleaned thoroughly if
required.
Any open ends or accessible surfaces shall be
protected against the infiltration of construction site
dust and humidity before interruptions of assembly
work.
7.2 Outdoor Air Inlet
Reference to VDI 6022 part1 outdoor-air inlets shall be
so positioned as to minimize any unfavorable effect on
the quality of the air taken in by local emission sources
such as exhaust air, smoke gas, olfactory, and other
disturbing sources (such as roads with heavy traffic,
garage doors, parking lots or bus stops, tarmac roofs,
open re-cooling plants, impacts emanating from
humans, alive and dead small animals).
Recirculation of exhaust air into the outdoor-air inlet
shall be avoided. Take into account the airflow around
the building, wind and meteorological conditions, roof
systems (such as attics) and any planned neighboring
buildings.
The outdoor-air inlet shall not be positioned close to,
and not in the main downwind direction behind, wet
cooling towers because of the danger of contamination
with microorganisms.
7.3 Exhaust-Air Outlet
Any short-circuit between exhaust air and outdoor-air
inlet shall be avoided. Positioning the exhaust-air outlet
above the roof and at a height greater than that of the
inlet opening. Sufficiently large distances between air
inlet and outlet openings and by blowing the exhaustair flow away from the outdoor-air inlet opening at
sufficient velocity
Page 15 of 20
Construction progress shall allow for commissioning of
the systems. (For instance: Rooms shall be free of
dust before the extract-air system is switched on.)
It is recommended to connect air-cooled
surfaces to the air duct system only after
the cleanliness of the completed
ventilating and air-conditioning system has
been checked and documented in an
appropriate manner.
Any drainage systems must not be
connected directly to the municipal
sewage system.
Ensure, by means of stepwise shutdown,
that the humidifier chamber is blown dry
before intended shutdowns.
It shall be possible to dimension, install,
and inspect or change air filters in such a
way that they minimize the carryover of
microorganisms and of inorganic and
organic dusts to downstream components
or into the rooms to which air is supplied;
on no account they must increase it.
It must be ensured that the filters
themselves do not become a source of
harmful or odorous substances, especially
due to microorganisms in the supply air.
Microbial growth on air filters can be
prevented or minimized by, e.g., limiting
the relative humidity.
8 – MAINTENANCE CHECKLIST
The checklist contains a general overview of the planning that facilitates the inspections and maintenance of the AHU.
Remember to de-energies all components and to ensure that the fan has stopped rotating, before the doors
and access covers are opened before inspections and maintenance take place.
Components
Panels
CASING
Doors
Actuator
General AHU Maintenance Check List
Check Points
Recommended Maintenance Operations
Contamination
Damage
Operation of Hinges & Locks
DAMPER
Check for seal span and crack
Installation
Check if correctly installed to the damper shaft
Fitting
Opening
Rotation
Bushing and Linkage
Operational
Flat Pre-filter
FILTER
Metallic filter
Vee filter
Control
Fins
COIL
Check if blades can open and close to require angle
Remove dirt from bushing and linkage rod with
compressed air
Check damper operational once power supply restored
Physical condition and seal
pressure drop
Check filter clip (frame) correctly installed
Check and remove pollution and dirt
Filter replacement depend to degree of contamination
All electrical connection
Airflow switch and
thermostat sensor
Contamination
Damage
Clean dirt with compressed air and check connection in
control box
Check the operation of airflow switch and thermostat
sensors
Clean dirt with compressed air
Check fin alignment and comb fins
Check gap and seal with silicon sealant to avoid fresh air
by-pass
Check gap and seal with silicon sealant to avoid fresh air
by-pass
Air by-pass
Headers
Seal
Water leakage
Eliminators
Contamination
Clean dirt with compressed air
Contamination
Clean dirt with vacuum cleaner
Water Flooding
Check and clean U-trap
Fan housing
Bearing
Contamination
Lubrication (re-grease type)
Wear
Blower
Contamination
Motor
Lubrication (re-grease type)
Drive (Pulleys
& Belts)
Belt tensioning
Fitting
Wear
Alignment
Isolators
Flexible
connection
HEAT
WHEEL
Check blades and rod bolts are tight
Coil Frames
Drain pan
FAN
Check seal integrity, remove dirt with compressed air
Check filter sitting (rail) correctly each other
Bag filter
ELECTRIC
HEATER
Check locks and hinges operational function
Door Seals
Seal and contamination
Blades
Remove contamination with water and mild house hold
soap
Remove rust and touch-up with anti-rust primer and paint
Rotor
Motor and
Drive
Fixing
Contamination
Crack and leak
Contamination
Incase tube leak, braze leak point
Check and remove dirt with compressed air
Check oil and re-grease every 6 months.
Check if physical bearing is good or replace with new
bearing
Check and remove dirt with compressed air
Check oil and re-grease every 6 months.
Check pulley fitting tightness to the shaft
Check tensioning and tighten the belt if required
Check if belt in good condition or replace with good belts
Check pulley and belt alignment
Check all bolts not loose, tighten the bolts if required
For spring isolators, check if rusted and touch-up with
anti-rust
Check if any damage or air leakage, replace new flexible
connector if required
Check and remove dirt with compressed air
Operational
Check rotor rotation
Operational
Check rotor speed and verify with design rpm
Wear and tear
Check if belts with enough tension
Page 16 of 20
Interval Month
1
3
6
12
9 – HYGENIC AHU MAINTENANCE CHECKLIST
The checklist contains a general overview of the planning that facilitates the inspections and maintenance of the
Hygienic AHU (Reference VDI 6022 Part 1 - Table 6) which are in addition to the normal maintenance checklist.
Components
AHU without
Humidification
Outdoor-Air Inlets
Central Air-Handling
Units / Unit Housings
Hygienic AHU Maintenance Check List
Check Points
Check for contamination, damage and corrosion
Clean and repair
Check for contamination, damage and corrosion
on the air side
Clean and repair
Check for water precipitation
Check spray nozzles for deposits
If number of CFUs > 1000
CFU/mL, clean, rinse and dry the
tray; disinfect; test quality of
supply water
15
days
Clean pump circuit
Repair
Function-check disinfection facilities
Repair
Check vapor distribution system for deposits
Check spray nozzles for deposits
During standstills **
If deposits have formed, extract
and clean unit, check region
downstream of mist collector
Clean and repair
Clean and repair steam humidifier
Clean
Clean or replace nozzles
Check drain
Clean and repair
Determine number of CFUs in the humidifier water;
Exception: steam humidifiers
If number of CFUs > 1000
CFU/mL, clean, rinse and dry the
tray; disinfect; test quality of
supply water
Function-check control valve
Repair
Check humidity limiter
Repair
Check for unacceptable contamination and
damage (leakages) and odors
Heat Exchanger
(Including Heat
Recovery Unit)
Clean and repair
Function-check conductivity sensor
Check for contamination, damage, microbial
growth and corrosion
Check for condensate precipitation in the
humidifier chamber
Fan
Clean and repair
Clean or replace nozzles
Check circulation pump for contamination and
deposits in the intake line, check condition and
functioning of filters
Check mist collector and flow rectifier for
contamination, damage, deposits, and corrosion
Silencers
24
Re-adjust
Completely empty and dry humidifier unit
Air Filters
Interval Month
3
6
12
Clean
Check empty housings for contamination, damage,
and corrosion
Check for contamination, damage, microbial
growth, and corrosion
Determine number of CFUs in the recirculating
water
Air Humidifiers
Operating Without
Recirculating Water
1
Routine maintenance possibly 36 months.
Function-check shutdown controls
Air Humidifiers
Operating With
Recirculating Water
Action, If Required
Check differential pressure
Change any affected air filters
Change filter stage
Maximum interval until first filter stage is to be changed
Maximum interval until second filter stage is to be changed
Check silencers for contamination, damage, and
Repair or replace; test with contact
corrosion
slides, if necessary
Clean and repair, check water
Check for contamination, damage, and corrosion
drain
Visual inspection of air-to-air plate heat
Clean, repair
exchangers for contamination, damage, corrosion
Visual inspection of air-to-air rotary heat
exchangers for contamination, damage, corrosion,
Adjust seals, clean, repair
and tightness
Visual inspection of directly heated heat
Replace seals, clean, repair
exchangers for tightness
Heaters: Check for contamination, damage,
Clean and repair, replace
corrosion, and tightness
Coolers: Check tube bundles, mist collectors and
condensate tray for contamination, corrosion,
Clean and repair
damage, and tightness
Function-check drain and siphon
Clean and repair
** During standstills (> 48h) in the absence of suitable disinfection facilities, or during times of operation when no humidification is required for more
than 48h.
Page 17 of 20
10 - AHU TROUBLESHOOTING GUIDE
PROBLEM
LESS AIR FLOW
PROBABLE CAUSE
RECOMMEDED SOLUTION
Low fan speed
Increase the fan speed by changing the pulleys
High external static than design
Check if the dampers are open and no block in the air passage
Duct layout
Ensure that the duct design is proper with no immediate bending /curve after
the fan discharge
Clogged / dirty coil
Clean the cooling coil
Clogged / dirty filter
Clean and replace filter
Overloaded motor
Reduce load or replace with larger motor
Improper line voltage
Check wiring, secure all connections, Check with the electricity supplier
MOTOR DRAW HIGH AMPS /
Worn bearing
OVER HEATS
Motor fan is clogged
MOTOR FAIL TO START
Relace bearing and seal
Remove fan cover, clean fan and replace cover
Three phase motor has one phase
Check wiring , secure all connections.
Blown fuse or open circuit braker
Replace fuse or reset circuit braker
Improper wiring or connection
Check wiring diagram supplied on the motor
Improper current supply
Compare actual power supply with the motor name plate
Mechanical failure
Determine the motor and drive turn freely without load. Check bearing and
lubrication
Short-circuited stater
Replace blown fuse. motor must be re-winded
Overloaded motor
Reduce load or replace with larger motor
MOTOR STARTS AND THEN Low voltage at motor terminal
FAILS OR MOTOR DOES Starter shorts when motor warm up
NOT COME UP TO THE
Line wiring too small
REQUIRED SPEED
60 hz motor connected to 50 hz
EXCESSIVE MOTOR NOISE
FREQUENT MOTOR
BEARING DAMAGE
LOOSE FAN BELT OR
SHORT BELT LIFE
FAN DOESNOT OPERATE
Check across ac line and correct voltage if possible
Replace starter
Relace with large sized wiring
Check the require frequency on motor rating plate
Motor mounting bolts are loose
Tighten motor mounting bolts
Rigid coupling connection
Replace with flexible connection
Worn motor bearing
Relace motor bearing and seal
Fan rubbing on fan cover
Remove and correct the fan housing in the motor
Excessive load due to over-tensioned drive
Check belt tension and load
Excessive load due to smaller motor pulley
Relace with large diameter pulley
Motor is poorly positioned
Adjust the motor to make good tension
Worn or damage belt
Replace belt and check alignment
Worn sheaves
Replace pulley
Misaligned pulleys
Realign the pulleys
Greese or oil on belts
Check for bearing leaks. clean belts and pulley
Belt slipping
Adjust tension
Electrical
Check motor fuses, electrical on-off switch, overload protector and voltage
Mechanical failure
Looks for broken belt or loose pulleys, make sure that the fan blades are not
touching the fan housing
Fan hitting inlet cone, cut-off or housing
Center fan in inlet cone, secure cut-off in housing. secure fan on shaft, repair
or replace the damaged parts
Drive belt not operating properly
Adjust belt tension, replace worn or broken belts and clean oily or dirty belts.
Check if all the belts are of the same size and type.
First start after relubrication. (regreasing)
Allow machine to cool down and restart
Over lubrication
Clean surface of grease and purge
No lubricants
Apply grease and check the bearing for damage
Excessive load or fan speed
Replace with large bearing / fan
Misaligned bearings
Correct alignement and check shaft level.
Air by-passing the coil
Prevent air bypass with blankoff plate
NOISY FAN
FAN BEARING -VERY HOT
LOW COIL CAPACITY/ LESS Coil tubes are blocked
Incorrect airflow
COOLING / HEATING
(CHILLED WATER / HOT
Incorrect gpm
WATER)
Incorrect water temperature
LOW COIL CAPACITY- DX
COILS
ELECTRIC HEATER-NOT
OPERATING
Clean and unblock the tubes
Check fan operating condition
Check water pumps,valves and lines for obstruction
Provide required water temperature
Incorrect airflow direction
Ensure that the airflow is in counter flow arrangement.
Air by-passing the coil
Prevent air bypass with blankoff plate
Coil tubes are blocked
Clean and unblock the tubes
Incorrect airflow
Check fan operating condition
Expansion valve not operating
Check sensing bulb location and the operation
Poor refrigerant distribution
Check for blockage in distributor and tubes
Wrong heater wiring and stages
Check the heater wiring and stages
Not proper airflow switch connection
Check the airflow switch direction, low-pressure & hi-pressure
Low voltage
Check the voltage
Contactors
Check the correct contactors and wiring size
Page 18 of 20
11 - MANDATORY START-UP CHECK LIST AND RECORD
IMPORTANT!
This page is a mandatory checklist & record – the check to be executed and data to be recorded for future reference incase of failure.
A copy of this checklist data has to be submitted to carrier or carrier representative. Completion of this checklist is a must for any field claim, no field support
will be provided for incomplete or blank checklists.
Before starting up the AHU ensure that the components have the correct connection voltage and connect them in
accordance with the regulations. The doors and access covers must be closed and the AHU must be earthed.
8.1 PRELIMINARY INFORMATION
MODEL NO:
JOB NAME:
SERIAL NO:
AHU LOCATION
START-UP DATE:
Indoor (
)
Outdoor (
)
TECHNICIAN NAME:
ADDITIONAL ACCESSORIES:
8.2 PRE-START-UP
PRE-START-UP Checklist
Yes
No
NA
No
NA
Review AHU Maintenance and Preservation Record for AHU stored for longer period (> 6 months) as specify in “3.2 Long term storage”
Review and record unit cleanliness, and check for corrosion
Filters & belts were kept separately indoor and in clean and good condition
Check and ensure fan bearing and grease in perfect condition
Remove packaging and any construction debris
TEAR ALONG THE DOTTED LINE
Internal and external panels are in good condition – no damage
Are damper operations correct?
Are proper air filters in place?
Is heating coil, if any, in correct connection side?
Is cooling coil, if any, in correct connection side?
Is there any leakage in the cooling coil?
Is the droplet eliminator, if required, already installed?
Has water been placed in drain pan to confirm proper drainage?
Insure drain trap connections / dimensions are correct
Insure the heat wheel is rotating in correct direction
Insure the heat wheel sealing is correctly installed
Insure the heat wheel gasket is correctly installed
Remove fan transport brackets
Untighten spring isolator bolt
Check fan bearings, shaft(s)
Hand turn fan to ensure no rubbing with housing.
Have fan and motor pulleys been checked for proper alignment?
Check if fan belts have proper tension and deflection? (Refer to unit sticker for values)
Are all wiring terminals to fan motors and heaters tight?
Check heater safety devices (airflow switch & auto / manual thermostat) are connected to MCC
Ensure air flow switch high pressure side should be connected to atmospheric pressure in draw through arrangement and in-case of blow
through arrangement should be connected to negative pressure
Check if airflow switch and thermostat sensor are functioning properly
Is duct connected to unit in proper way? ( straight duct after fan discharge is 2.5 fan diameter )
Verify wiring is correct for application (voltage, etc.) per component label
8.3 START-UP
If this unit is used for construction conditioning without ductwork, ensure balancing is redone and filters replaced once construction is complete.
Yes
Ensure correct fan rotation.
Measure and record actual fan rpm/absorbed motor kW/total fan static pressure and plot on fan curve.
Ensure fan and motor operating at designed operating point.
Ensure all water inside air handler is in condensate pan.
Check for vibration levels.
After air and water balance and at least 10 minutes running time, record the following measurements:
Check indoor fan speed RPM
Air Entering Condition ( DB / RH / WB)
Air Leaving Condition ( DB / RH / WB)
Entering / Leaving water temp.
Page 19 of 20
Manufacturer reserves the rights to discontinue or change at any time, specifications or designs without notice and without incurring any obligations.
Supersedes Version: 39HQMIOM-06
Catalog Number: 39HQMIOM-07
Page 20 of 20
Effective Date: 02-02-2021
Phase: 50Hz & 60Hz