LG AK-C3608H00 User manual

INSTALLATION MANUAL
SINGLE PACKAGE TYPE AIR CONDITIONER
AIR
CONDITIONER
Please read this installation manual completely before installing the product.
Installation work must be performed in accordance with the national wiring
standards by authorized personnel only.
Please retain this installation manual for future reference after reading it
thoroughly.
www.lg.com
Copyright © 2022 LG Electronics Inc. All Rights Reserved.
MFL71887801
Rev.01_032522
ENGLISH

• Do not cool excessively indoors. This may be harmful for your health and may consume more
electricity.
• Block sunlight with blinds or curtains while you are operating the air conditioner.
• Keep doors or windows closed tightly while you are operating the air conditioner.
• Adjust the direction of the air flow vertically or horizontally to circulate indoor air.
• Speed up the fan to cool or warm indoor air quickly, in a short period of time.
• Open windows regularly for ventilation as the indoor air quality may deteriorate if the air
conditioner is used for many hours.
• Clean the air filter once every 2 weeks. Dust and impurities collected in the air filter may block the
air flow or weaken the cooling / dehumidifying functions.
For your records
Staple your receipt to this page in case you need it to prove the date of purchase or for warranty
purposes. Write the model number and the serial number here:
Model number :
Serial number :
You can find them on a label on the side of each unit.
Dealer’s name :
Date of purchase :
Here are some tips that will help you minimize the power consumption when you use the air
conditioner. You can use your air conditioner more efficiently by referring to the instructions
below:
This appliance is not intended for use by persons (including children) with reduced physical,
sensory or mental capabilities may be different or reduced, or lack of experience or knowledge,
unless such persons are supervision or training to operate the appliance by a person responsible
for their safety. Children should be supervised to ensure they do not use the devices as a toy.
TIPS FOR SAVING ENERGY
TIPS FOR SAVING ENERGY
2
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This device is not accessible to the public generally
WARNING
!

3
SAFETY INSTRUCTIONS
ENGLISH
WARNING
This indicates that the failure to follow the instructions can cause serious injury or death.
CAUTION
This indicates that the failure to follow the instructions can cause the minor injury or damage to
the product.
This symbol is displayed to indicate matters and operations that can cause risk.
Read the part with this symbol carefully and follow the instructions in order to avoid risk.
!
!
!
SAFETY INSTRUCTIONS
The following safety guidelines are intended to prevent unforeseen risks or damage from unsafe or
incorrect operation of the appliance.
The guidelines are separated into ‘WARNING’ and ‘CAUTION’ as described below.
WARNING
• Installation or repairs made by unqualified persons can result in hazards to you and others.
• Installation shall be in accordance with national standards of electrical appliances.
• The information contained in the manual is intended for use by a qualified service technician familiar
with safety procedures and equipped with the proper tools and test instruments.
• Failure to carefully read and follow all instructions in this manual can result in equipment
malfunction, property damage, personal injury and/or death.
Installation
• Do not use a defective or underrated circuit breaker. Use this appliance on a dedicated circuit.
- There is risk of fire or electric shock.
• For electrical work, contact the dealer, seller, a qualified electrician, or an Authorized Service Center.
- Do not disassemble or repair the product. There is risk of fire or electric shock.
• Always ground the product.
- There is risk of fire or electric shock.
• Install the panel and the cover of control box securely.
- There is risk of fire or electric shock.
• Always install a dedicated circuit and circuit breaker.
- Improper wiring or installation may cause fire or electric shock
• Use the correctly rated circuit breaker or fuse.
- There is risk of fire or electric shock.
• Use the specified wires to connect the unit.
- There is risk of fire or electric shock.
• Do not install, remove, or re-install the unit by yourself (customer).
- There is risk of fire, electric shock, explosion, or injury.
• Be cautious when unpacking and installing the product.
- Sharp edges could cause injury. Be especially careful of the case edges and the fins on the
condenser and evaporator.
• For installation, always contact the dealer or an Authorized Service Center.
!

• Do not install the product on a defective installation stand.
- It may cause injury, accident, or damage to the product.
• Be sure the installation area does not deteriorate with age.
- If the base collapses, the air conditioner could fall with it, causing property damage, product failure,
and personal injury.
• Use a vacuum pump or Inert (nitrogen) gas when doing leakage test or air purge. Do not compress
air or Oxygen and Do not use Flammable gases. Otherwise, it may cause fire or explosion.
- There is the risk of death, injury, fire or explosion.
• When using Thermostat, be sure to use double insulated thermostat.
Operation
• Take care to ensure that power cable could not be pulled out or damaged during operation.
- There is risk of fire or electric shock.
• Do not place anything on the power cable.
- There is risk of fire or electric shock.
• Do not touch(operate) the product with wet hands.
- There is risk of fire or electrical shock.
• Do not place a heater or other appliances near the power cable.
- There is risk of fire and electric shock.
• Do not allow water to run into electric parts.
- It may cause failure of the product or electric shock.
• Do not store or use flammable gas or combustibles near the product.
- There is risk of fire or failure of product.
• Do not use the product in a tightly closed space for a long time.
- Oxygen deficiency could occur.
• When flammable gas leaks, turn off the gas and open a window for ventilation before turn the
product on.
- Do not use the telephone or turn switches on or off. There is risk of explosion or fire
• If strange sounds, smell or smoke comes from product. Turn the circuit breaker off or disconnect
the power supply cable.
- There is risk of electric shock or fire.
• Stop operation and close the window in storm or hurricane. If possible, remove the product from the
window before the hurricane arrives.
- There is risk of property damage, failure of product, or electric shock.
• Do not open the panel of product during operation. (If the unit has the electrostatic filter, Do not
touch it.)
- There is risk of physical injury, electric shock, or product failure.
• When the product is soaked (flooded or submerged), contact an Authorized Service Center.
- There is risk of fire or electric shock.
• Be cautious that water could not enter the product.
- There is risk of fire, electric shock, or product damage.
• Ventilate the product from time to time when operating it together with a stove, etc.
- There is risk of fire or electric shock.
• Turn the main power off when cleaning or maintaining the product.
- There is risk of electric shock.
• When the product is not be used for a long time, turn off the circuit breaker.
- There is risk of product damage or failure, or unintended operation.
• Take care to ensure that nobody could step on or fall onto the unit.
- This could result in personal injury and product damage.
SAFETY INSTRUCTIONS
4
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SAFETY INSTRUCTIONS
CAUTION
Installation
• Always check for gas (refrigerant) pressure after installation or repair of product.
- Low refrigerant levels may cause failure of product.
• Install the drain hose to ensure that water is drained away properly.
- A bad connection may cause water leakage.
• Keep level even when installing the product.
- To avoid vibration or water leakage.
• Do not install the product where the noise or hot air from the outdoor unit could damage the
neighborhoods.
- It may cause a problem for your neighbors.
• Don't use people to lift and transport the product.
- Avoid personal injury.
• Do not install the product where it will be exposed to sea wind (salt spray) directly.
- It may cause corrosion on the product. Corrosion, particularly on the condenser and evaporator
fins, could cause product malfunction or inefficient operation.
• Do not let the air conditioner run for a long time when the humidity is very high and a door or a
window is left open.
- Moisture may condense and wet or damage furniture.
• Do not install the unit in potentially explosive atmospheres.
Operation
• Do not expose the skin directly to cool air for long periods of time. (Don't sit in the draft.)
- This could harm to your health.
• Do not use the product for special purposes, such as preserving foods, works of art, etc. It is a
consumer air conditioner, not a precision refrigeration system.
- There is risk of damage or loss of property.
• Turn on the power at least 6 hours before starting operation.
- Starting operation immediately after turning on the main power switch can result in severe damage
to internal parts. Keep the power switch turned on during the operational season.
!
5
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6TABLE OF CONTENTS
ENGLISH
2TIPS FOR SAVING ENERGY
3SAFETY INSTRUCTIONS
7INTRODUCTION
7Features
9DIMENSIONAL DATA
10 INSTALLATION OF UNIT
10 General Statement
10 Safety Issues
11 Inspection for damage
11 General
12 Location of unit
13 Installation Clearance
14 Rigging Instructions
14 Condensate Drain Connection
14 Duct Connection
15 Electric Heaters
15 Crankcase Heater
15 Pump Down Control
16 Electronic Wiring
17 MAINTENANCE INSTRUCTIONS
17 Airflow Adjustment
17 Crankcase Heater
17 Cleaning of Coils & Filters
18 Belt Tension Testing Procedure instruction
18 Belt Tension Testing Procedure
19 Preventive maintenance schedule
20 TROUBLE SHOOTING
24 INSTALLATION OF THERMOSTAT
24 INDEX
25 Specifications
26 Thermostat Installation
28 Installer Menu
29 Test Equipment
30 USING THE THERMOSTAT
30 Thermostat Overview
31 User Menu
31 Thermostat Operation
32 TROUBLESHOOTING
34 INSTALLER SETTING
34 Final Installation Checklist and Maintenance
36 Installation guide at the seaside
37 Instruction Sheet
TABLE OF CONTENTS

INTRODUCTION 7
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Features
Single packaged Units have been developed & produced to provide not only the ultimate indoor
comfort, but also to guarantee long & trouble free operations.
Here lies the reason for the choice of only the highest quality components and design strategist
to meet the most important objective such as:
• Efficiency
• Reliability
• Flexibility
• Easy Installation
• Serviceability
• Affordability
INTRODUCTION

8INTRODUCTION
ENGLISH
- Refrigerant : R410A.
- Factory Wired with Single Point Power Input.
- Scroll Compressor.
- High Pressure & Low Pressure Safety
Switches.
- Power Controller, High/Low Voltage, Phase
Loss/Reversal Protection.
- All units are provided with ON-Delay timers
for Anti-short cycling.
- Internal Motor Protection for 3Ø Indoor &
Outdoor motors.
- All Units are designed to operate with 24V
Universal Thermostat.
- Thermostatic Expansion Valve
- Condenser Fans are Propeller type Direct
Driven, draw through Vertical Discharge with
fan guard mounted to the Panel.
- Condenser & Evaporator Coils made of
Copper tubes and Aluminum fins.
- Weather resistant steel cabinet, qualified for
1000 Hours of Salt Spray test.
- 2” Disposable Air Filter
- Anti Corrosion Heresite Treatment on
condenser coil HEX
- Hydrophilic coating on Evaporator HEX
- IP 55 Class F for Blower Motor
- Electric Heater.
- Overload External protection for Blower
Motor.
- Anti Ice thermostat.
- Copper Fins for Evaporator & Condenser coil.
- Stainless Steel Drain Pan.
- Filter Differential pressure Switch. Overload
External Protection for Compressor.
- Compressor Alternating Switch.
- Hour Run Meter.
- Fan Cycling Switch.
- Rotolock Compressor
- Circuit breaker (MCB) for Compressor &
Blower Motor.
- Pump Down System.
- Dual Adjustable Pressure Switch.
- Hot Gas Bypass (with Solenoid). Pressure
Gauges.
- Oversized Blower Motor & Alternate Drive
Package.
- PCB Controller.
- Advanced Microprocessor Controller.
Adjustable Voltage Monitor.
- UV Light.
- Adjustable Pressure Switch.
- VFD for Blower Motor.
- Soft Starter for Blower Motor.
- Volt free Contacts for Compressor & Blower
ON/OFF/TRIP Status.
- Fire Alarm Interlock
- Crankcase Heater for Compressor
- Sight Glass
- 2” Synthetic Filter
Standard Features Optional Features

DIMENSIONAL DATA 9
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Single packaged Units are designed for outdoor mounting with vertical condenser discharge.
They can be located either at ground level or on roof.
Each unit contains an operating charge of Refrigerant as shipped.
S.NO LEGENDS
1 Cond Fan Motor & Grill
2 Condensor Coil
3 Compressor
4 Supply Air Opening
5 Control Panel Access
6 Compressor Access
7 Supply Air Blower
8 Evaporator Coil
9 Pre Filter
10 Blower Motor
11 Blower & Coil Access
12 Filter Access
DIMENSIONAL DATA
TOP VIEW
FRONT VIEW RHS VIEW
SUPPLY
AIR
RETURN
AIR
LHS VIEW
[Unit : mm]

10 INSTALLATION OF UNIT
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General Statement
Single packaged Units have been designed & built for the optimum performance. However, it is
required that you become well acquainted with good practices for the proper
installation/operation/ and maintenance procedures in order to ensure a safe trouble free
operation, year after year.
Please read through the whole manual contents before you attempt to install/operate/ and
maintain the unit.
Most of the procedures described in this manual require certain skills and experience. The
installation and other maintenance procedures should be performed only by highly skilled and
experienced technicians. The end user’s role should be limited to the cleaning of the filter.
Single packaged Units can be supplied, depending on the End User requirement, as the basic
“Cool Only” version, or the “Heat & Cool” version (with electric heater module).
Warranty
Single packaged Units are covered by the standard warranty terms against any manufacturer
defect. Should you encounter any problem that falls under the warranty terms.
Safety Issues
When performing any task pertaining to the installation and maintenance of the unit, the skilled
technician should observe all the applicable safety measures (wear of safety helmet, boots,
gloves, and goggles. Use of proper handling materials for brazing and use of wet cloth for
quenching. A fire extinguisher should be easily accessible etc.). He should also read all the
instructions and information in this Manual prior to attempting to perform any installation or
servicing of the unit.
All applicable local codes should also be observed.
The PQ units operate on a high voltage with moving parts (at high speed) which can lead to
serious injuries and/or damage to the unit. Never attempt to service the unit unless the main
electrical power supply has been disconnected.
WARNING
!
Extra care should be observed when installing, test running, adjusting, servicing, or
maintaining the unit as the hazard of explosion, fire, electrical shock, and potential personal
injury and property damage are present.
CAUTION
!
INSTALLATION OF UNIT

11
INSTALLATION OF UNIT
ENGLISH
Inspection for damage
The unit should be carefully inspected visually for any sign of physical damage due to
mishandling. Whenever a damage is detected, please indicate it on the corresponding delivery
note before you sign it.
General
These units are shipped completely assembled, charged, and wired. They do not require any field
installation of refrigerant tubing. Units require external power, thermostat wiring, condensate
drain piping and ducting as applicable.
Size of unit for an installation should be based on a heat gain calculation made according to
applicable standards. Units must also be installed in accordance with regulations of the “National
Fire Protection Association” and local electrical codes. Where local regulations conflicts with the
instructions in this manual, installer should adhere to local standards. Prepare your concrete pad
or steel stand based on the corresponding dimensions. Remove shipping protective covers and
wooden crating and lift unit from base and place in position with suitable rubber vibration
isolators.
All field installed accessories are to be installed by the customer with necessary reinforcements
as required.

12 INSTALLATION OF UNIT
ENGLISH
Do not install the unit as indoor unit, install it in an open area, and unit air inlets must not be
located near exhaust vents or other source of contaminated air.
CAUTION
!
Location of unit
When selecting the location for the unit, the following points should be kept in mind:
1. Provisions for a concrete pad or steel stand base.
2. That the terrain allows for drainage away from the unit.
3. If the unit is to be roof mounted, inspect the roof for load bearing capacity. The roof should
have sufficient structural strength to carry the weight of the unit.
4. Install unit on vibration isolation pads, i.e. on rubber mounting pads
5. Availability of electric power.
6. To position the unit for unrestricted air circulation of the condenser air inlet and to prevent any
possibility of air recirculation from the condenser fan discharge air (see figure on next page).
7. Check minimum clearances required for your unit, with regard to walls, or other obstructions
(see figure on next page).
8. Air cooled equipment should not be installed under low structural overhangs which can cause
condenser air recirculation or restriction. Observe minimum of clearance (see figure on next
page).
9. Care should be taken to prevent air from other sources from entering condenser, if this air is at
a high temperature.
10. Level the unit on its final location and be sure that the levelling tolerance is ±5mm per linear
meter in any direction.

INSTALLATION OF UNIT 13
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NOTE
All dimensions are in (mm).
1,500
1,500
1,500
3,000
Installation Clearance
Straight Wall
Corner Wall

14 INSTALLATION OF UNIT
ENGLISH
Condensate Drain Connection
Use standard PVC pipe with NPT connection for the condensate drain. Provide a ‘P’ trap
immediately at the condensate drain connection.
Piping has to be sloped away from the unit.
Remember to remove the drain hole plug before operating the unit. Avoid bends & elbows.
Duct Connection
The units can be connected to the ducting in horizontal configuration. Connect ducting using
flexible duct connection. The duct should be properly designed and the drive package should
match the required CFM & corresponding external static pressure.
LIFT LIFT
Compressor
End
Spreader bar
Proper clearance to be provided
Must be 2” nominal pipe thru unit
for slings to avoid base damage.
All panels should be in place when rigging.
CAUTION
!
NOTE
Avoid abrupt changes in size and/or direction of duct to ensure proper unit performance.
Rigging Instructions
Attention to riggers
• Insert 2” nominal pipe through holes in the base rail as shown in the figure below for slings.
• Holes in base rail are centered around the unit center of gravity.
• Use wooden pallet or spreader bar when rigging, to prevent the slings from damaging the unit.
• Rollers may be used to move the unit on the roof or ground.

INSTALLATION OF UNIT 15
ENGLISH
Electric Heaters
Electric heater kit is installed as an externally mounted kit at the supply air opening.
Crankcase Heater
The crankcase heater is provided to hold the compressor oil reservoir at higher temperature than
the coldest part in the system.
Power must be supplied to crankcase heater for a minimum of 12-hours prior to system start-up.
If power is off for 6-hours or more, crankcase heater must be energized for 12-hours before
operating the system. Otherwise compressor damage may result.
Pump Down Control
If the unit is provided with pumpdown system, then a solenoid type valve is installed in the liquid
line ahead of expansion valve to prevent flow of refrigerant into the evaporator during off cycle.
The controller is wired to solenoid valve which energize in cooling and opening the valve.
Whenever the thermostat temperature is satisfied, the solenoid will close followed compressor
off after pumping the refrigerant from low side of the system until the low pressure switch open
the control circuit.

16 INSTALLATION OF UNIT
ENGLISH
380-415 V 3~ 50 Hz
380-400 V 3~ 60 Hz
Capacity (RT) Voltage range (V) MCA (A)
30 342~456 V 96
35 342~456 V 115
40 342~456 V 125
Capacity (RT) Voltage range (V) MCA (A)
30 342~440 V 125
Air
Conditioner
Main power source
Circuit Breaker
Use a circuit breaker
or time delay fuse.
Cable Type H07RN-F
• The circuit diagram is not subject to
change without notice.
• Be sure to connect wires according to
the circuit diagram.
• Connect the wires firmly, so that not to
be pulled out easily.
• Connect the wires according to color
codes by referring the circuit diagram.
• If the supply cord is damaged, it must
be replaced by a special cord or
assembly available from the
manufacturer of its service agent.
CAUTION
!
• Provide a circuit breaker between power
source and the unit as shown below.
CAUTION
!
• The power cord connected to the
outdoor unit(Main Power supply cable)
should be complied with the following
specifications (Cable type approved by
HAR or SAA).
• Select the wire size based on the MCA.
CAUTION
!
Use round crimp-style terminals for
connecting wires to the terminal block.
Electric wire
Round crimp-style terminal
Attach insulation sleeve
WARNING
!
• Be sure to have authorized electrical
engineers do the electric work using
special circuits in accordance with
regulations and this installation manual.
If power supply circuit has a lack of
capacity or electric work deficiency, it
may cause an electric shock or fire.
Electronic Wiring
Follow ordinance of your governmental
organization for technical standard related to
electrical equipment, wiring regulations and
guidance of each electric power company.
NOTE
Pipes and wires should be purchased
separately for installation of the product.

MAINTENANCE INSTRUCTIONS 17
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Airflow Adjustment
The airflow could be adjusted by adjusting pulleys of blower motor or belt tension with proper
mounting and alignment of pulleys:
- Refer to fan performance tables in the catalog for selecting applicable airflow, RPM and brake
horse power at specified static pressure.
- Select the appropriate drive as per motor and blower characteristic in the catalog.
- The set screw shall be loosened to make the pulley moving.
- Adjust pulley’s diameter, opening counter clockwise to reduce RPM and further reduce airflow,
while closing clockwise increases RPM and airflow.
- Tighten the set screw and then install the belts.
- Test the unit operating airflow for further adjustment.
Crankcase Heater
Periodic checking for proper operation or crankcase heater is highly recommended as follows :
a) Check continuity of the heater using multimeter device.
b) Check grounding of the heater by Meggar device (to prevent electrical hazards).
c) Observe whether the heater is warming down the compressor near the oil sump.
Cleaning of Coils & Filters
- Turn off the power supply.
- Take out access panel of evaporator coil.
- Remove the filter from its access panel.
- Protect electrical components and motors from water washing.
- Clean the coil by flushing water by pressure washer followed by compressed air from supply to
return direction.
- Filter shall be cleaned every six month, in some hygienic application it is recommended for
replacement.
- Cleaning drain pan and trap is recommended once in a year to prevent bacteria growing under
the coil.
MAINTENANCE INSTRUCTIONS

18 MAINTENANCE INSTRUCTIONS
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Belt Tension Testing Procedure
Belt tension checker Measure the belt deflection force
NOTE
Tension new drives at the maximum deflection force recommended. Check the tension at
least two times during the first day’s operation as there normally will be a rapid decrease in
belt tension until belts have run in. Check the tension periodically after the first day’s
operation and keep tension at which the belts will not slip under the peak load conditions.
Shafts must be adequate for the tensions required.
Small
“0”
Ring
Force Scale
Span Scale
Large
“0”
Ring
Deflection =
Belt Span
Belt Span
64
Belt Tension Testing Procedure instruction
To determine the lbs. force required to tension a drive, you simply do the following:
1. Measure the Belt span as shown.
2. Divide belt span by 64 to get belt deflection needed to check tension.
3. Set large “0” ring on span scale at required belt deflection. This scale is in 1/16” increments.
4. Set small “0” ring at zero on the “Force Scale”(plunger).
5. Place the larger end of the tension checker squarely on one belt at the center of the belt span.
Apply force on the plunger until the bottom of the large “0” ring is even with the top of the
next belt or with the bottom of a straight edge laid across the sheaves.
6. Read the force scale under the small “0” ring to determine force required to give the needed
deflection.
7. Compare the force scale reading with the correct value for the belt style and cross section
used, as given in table on next page. The force should be between the minimum and
maximum values shown.
8. If there is too little deflection force, the belts should be tightened. If there is too much
deflection force, the belts should be loosened.

MAINTENANCE INSTRUCTIONS 19
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*If fiberglass filters used, replace it yearly.
Belt
Preventive maintenance schedule
NOTE
Always observe for abnormal noise or vibration.
Disconnect power supply and allow all rotating parts to stop before servicing the unit.
CAUTION
!
Belt Type Belt Cross
Section
Small Pulley
Pitch DIA.(P.D.) Range
Deflection Force-LBS.
Minimum Maximum
- 3 L
1.25 - 1.75
2 - 2.25
2.5 - 3
1/2
5/8
3/4
5/8
7/8
1-1/8
A 4 L
2.1 - 2.8
3 - 3.5
3.7 - 5
1-1/8
1-1/2
1-7/8
1-5/8
2-1/8
2-5/8
B 5 L 3 - 4.2
4.5 - 5.2
2
2-3/8
2-7/8
3-3/8
ITEM
Frequency of Maintenance,
Month ITEM (First 4 Years)
612
Clean air filter (Aluminum)* X
Pressure wash condenser & cooling coil as required X
Check blower belt, tension, wear tear / replace if required X
Check alignment of pulleys X
Clean drain pan, drain pipe X
Clean blower wheel X
Check for loose bolts/screws & tighten as necessary X
Check all electrical controls, components, wiring terminals, tec…,
for sparks, over heat, loose connections / repair or correct X
Check for rusted / paint X
Check all temperature, pressure readings as applicable and satisfy
the operation performance X
Run test all motors and check the amperage X
Grease / oil as required X
Check vibration isolators X
Clean and fix thermal bulbs in the correct location. Insulate it. X
Check canvass connections, insulation damage X
Maintenance tools / equipment required
- Standard : Screw drivers (Slot & Phillips), adjustable wrenches, pliers, refrigeration wrenches &
socket set wrenches, pulley puller, etc.
- Special : Manifold gauge set, charging cylinder, belt tension checker, leak detector, vacuum
pump with electronic gauges, Thermometer, hook type ammeter/voltmeter/ohmmeter
and oxy-acetylene brazing set etc.

20 TROUBLE SHOOTING
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TROUBLE SHOOTING
Symptom Causes Check & Corrective measure
Thermostat shows no
display
1. Power off / Blown fuse
2. Faulty field wiring
3. Loose connection
4. Defective thermostat
1. Check the power. Switch ON the circuit
breaker. Replace fuse if it blown.
2. Check wiring against diagram.
3. Check and correct it.
4. Replace it.
Thermostat LCD
panel display is not
bright & does not
function properly
1. Battery life is over 1. Replace battery
Blower not running,
compressor short
cycles
1. Blower belt slipped / not fixed
2. Faulty wiring
3. Burned wiring
4. Defective blower motor
contactor
5. Defective blower motor
1. Correct belt. Check tension and alignment.
2. Check wiring against diagram.
3. Check and correct it.
4. Replace it.
5. Replace it.
Blower running, no
sufficient air
1. Wrong rotation (Applicable
initial start up / or after a power
failure), 3 phase motor
1. Check the rotation of blower, interchange
phase of blower motor from blower motor
contactor.
Blower running, but
with not enough
supply air
1. Loose Belt
2. Variable pulley wide open
3. Return air obsturcted
4. High static pressure
5. Improper pulley selection
6. Closed dampers / improper air
balance
7. Dirty filter
8. Dirty cooling coil
1. Adjust it & check belt tension.
2. Adjust the pitch of the pulley.
3. Check and remove the obstructions.
4. Verify static pressure and fan performance
data.
5. Change pulley (if blower motor ampere
within rated load.)
6. Check all dampers opened properly.
Balance air.
7. Clean it.
8. Clean it.
Blower running and
delivers excess air
1. Variable pulley needs more
tightening
2. Improper pulley / motor
selection
3. Low external static pressure
1. Adjust the pitch of the pulley.
2. Select suitable combination.
3. Check the duct design.
Blower runs,
compressor not
working
1. Safety circuit open due to low
suction pressure, high
discharge pressure, overload
protector
2. Defective compressor
contactor
3 Burned wiring
4. Defective compressor
1. Re-set the unit and determine the reason.
Check high & low pressure (refer to
symptom for "low/high suction pressure &
high discharge pressure").
2. Replace it.
3. Check and replace it.
4. Replace it.