LG PAHCMS000 User manual

SERVICE MANUAL
AIR
CONDITIONER
Please read this manual carefully before operating
your set and retain it for future reference.
Applied(AHU)
COMMUNICATION KIT
PAHCMR000, PAHCMS000
CONFIDENTIAL
www.lg.comP/NO : MFL70041201
Copyright © 2017 LG Electronics Inc. All rights reserved. Only training and service purposes.

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Ventilation System Service Manual
TABLE OF CONTENTS
Safety Precautions..................................................................................................3
Standards for Model ..............................................................................................6
Functions & Accessory ..........................................................................................7
Wiring Diagram ......................................................................................................8
Disassembly Diagram (Deal Drawing) ..................................................................9
Troubleshooting ...................................................................................................13

Safety Precautions
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1.1 Cautions in Repair
To prevent injury to the user or other people and property damage, the following instructions must be followed.
nIncorrect operation due to ignoring instruction will cause harm or damage. The seriousness is classified by the
following indications.
This symbol indicates the possibility of death or serious injury.
This symbol indicates the possibility of injury or damage to properties only.
nMeanings of symbols used in this manual are as shown below.
Be sure to disconnect all remote electric power supplies before servicing. Internal
components and circuit boards are at main potential when the equipment is
connected to the power cables. This voltage is extremely dangerous and may
cause death or severe injury if come in contact with it.
When removing the front panel or cabinet, execute short-circuit and discharge
between high voltage capacitor terminals. If discharge is not executed, an electric
shock is caused by high voltage resulted in a death or injury.
Be sure to provide the grounding when repairing the equipment in a humid or wet
place, to avoid electrical shocks.
Be sure not to do.
Be sure to follow the instruction.
Dangerous Voltage
Be sure to provide grounding.
Safety Precautions

Safety Precautions
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Do not use a defective or underrated circuit breaker. Use the correctly rated
breaker and fuse. Otherwise there is a risk of fire or electric shock.
Install the panel and the cover of control box securely. Otherwise there is risk of
fire or electric shock due to dust, water etc.
Comm.Kit/outdoor wiring connections must be secured tightly and the cable should be
routed properly so that there is no force pulling the cable from the connection
terminals. Improper or loose connections can cause heat generation or fire.
Do not touch, operate, or repaire the product with wet hands. Hoding the plug by
hand when taking out. Otherwise there is risk of electric shock or fire.
Do not turn on the breaker or power under condition that front panel, cabinet, top
cover, control box cover are removed or opened.
- Otherwise, it may cause fire, electric shock, explosion or death.
Be sure to earth the air conditioner with an earthing conductor connected to the
earthing terminal.
Do not tilt the unit when removing panels. Otherwise, the water inside the unit can
spill and wet floor.
Be sure to turn off power switch before connect or disconnect connector, or parts
damage may be occurred.

Safety Precautions
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1.2 Inspections after Repair
Check to see if the parts are mounted correctly and wires are connected.
Improper installation and connections can cause an electric shock or an injury.
Check the installation platform or frame has corroded. Corroded installation
platform or frame can cause the unit to fall, resulting in injury.
Be sure to check the earth wire is correctly connected.
After the work has finished, be sure to do an insulation tset to check the
resistance is 2[Mohm] or more between the charge section and the non-charge
metal section (Earth position). If the resistance value is low, a disaster such as a
leak or electric shock is caused at user’s side.
Check to see if the terminal block is not dirty or loose. If terminal block is dust or
loose it can cause an electrical shock or fire.
Do not use a joined power cable or extension cable, or share the same power
outlet with other electrical appliances. otherwise, it can cause an electrical shock,
excessive heat generation or fire.
Do not insert hands or other objects through the air inlet or outlet while the
product is operating. There are sharp and moving parts that could cause
personal injury.
Do not block the inlet or outlet of air flow. It may cause product failure

Standards for Model
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Standards for Model
P AHCM S 000
Series
000 : Multi V, Single
Model Classfication
R :Return Air Control
S :Supply Air Control
Model Type
AHCM : AHU Comm. Kit
Accessory Type

Functions & Accessory
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Functions & Accessory
1. Main Functions
2. Accessory
[Note]
• O: Applied, • X: Not applied
Accessory model name : Installed at field, ordered and purchased separately by the corresponding model name, supplied with separate
package.
Category Functions Model
Individual control Remote controller PQRCVSL0 / PQRCVSL0QW (Optional)
Functions
Model
PAHCMS000 PAHCMR000
Input
Operation (on/off)
O O
Operation mode (cool/heat)
O O
Output
Operation (on/off) O O
Defrost signal O O
Alarm signal O O
Comp. status O X
ODU Capacity control O X
3rd Party DDC interlock O X

Wiring Diagram
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Wiring Diagram
Model : PAHCMR000
Model : PAHCMS000

Wiring Diagram
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nMain Module
nMain Module

Disassembly Diagram (Deal Drawing)
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Disassembly Diagram (Deal Drawing)
Model : PAHCMR000
263230A
263230B
263230C
247810A
W4810
137215C
137215A
137215B

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Disassembly Diagram (Deal Drawing)
SVC Parts List
Location
No. Item Part No. Quantity(Volume/Amount) SVC Remarks
PAHCMR000
137215A Panel Assembly,Control AGL75873901 1 R
137215B Panel Assembly,Control AGL75874301 1 R
137215C Panel Assembly,Control AGL76255601 1 R
W4810 Bracket MAZ64606301 1 R
247810A Controller Assembly ACM75139001 1 R Comm. PCB
263230A Thermistor Assembly,NTC EBG62485901 1 R
263230B Thermistor Assembly,NTC EBG62485902 1 R
263230C Thermistor Assembly,NTC EBG62485903 1 R

Disassembly Diagram (Deal Drawing)
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Model : PAHCMS000
137215B
W6631
137215C
137215A
263230A
263230B
247810B
263230C 247810A
W4810

Disassembly Diagram (Deal Drawing)
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SVC Parts List
Location
No. Item Part No. Quantity(Volume/Amount) SVC Remarks
PAHCMS000
137215A Panel Assembly,Control AGL75874001 1 R
137215B Panel Assembly,Control AGL75874302 1 R
137215C Panel Assembly,Control AGL76255701 1 R
W4810 Bracket MAZ64606301 1 R
247810A Controller Assembly ACM75139001 1 R Comm. PCB
247810B Controller Assembly ACM75098801 1 R Main PCB
263230A Thermistor Assembly,NTC EBG62485901 1 R
263230B Thermistor Assembly,NTC EBG62485902 1 R
263230C Thermistor Assembly,NTC EBG62485903 1 R
W6631 Harness,Multi EAD64109806 1 R

Troubleshooting
Troubleshooting
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1.1 Error Indicator (Comm.Kit)
[Error Code (Comm.Kit)]
Display Number Error Item Cause of Error
CH 01 Room Temperature Temperature sensor disconnection or short
circuit on Room or RA of AHU
CH 02 Pipe In Temperature sensor error Temperature sensor disconnection or short
circuit on pipe inlet of AHU
CH 03 Communication error between wired
remote controller and Comm. Kit
No communication signal for more than 3
minutes from wired remote controller to the
Comm. Kit
CH 05 Communication error between Comm.
Kit and Outdoor Unit
No communication signal for 5 minutes
continuously from Comm. Kit to Outdoor Unit
CH 06 Pipe Out Temperature sensor error Temperature sensor disconnection or short
circuit on pipe outlet of AHU
Problem Cause Remedy
AHU Communication Kit
does not work
No power supply Check the electrical connection and voltage of the
power supply.
Wiring is wrong
Check the electrical connection of the
Communication Kit (Refer to the circuit diagram of
the Communication Kit)
AHU Communication
Kit is broken Check the electrical and mechanical part.
Error Indicator
- This function indicates types of failure in self-diagnosis and occurrence of failure for air condition.
- Error mark is displayed on wired remote controller, and 7-segment LED of outdoor unit control board as shown in
the table.
- If more than two troubles occur simultaneously, lower number of error code is first displayed.
- After error occurrence, if error is released, error LED is also released simultaneously.

Troubleshooting
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Display Title Cause of Error
Outdoor unit related error
2 1 1 Outdoor unit Inverter Compressor IPM
Fault Outdoor unit Inverter Compressor Drive IPM Fault
2 2 1 Inverter Board Input Over Current(RMS) of
Outdoor Unit Outdoor unit Inverter Board Input Current excess (RMS)
2 3 1 Outdoor unit Inverter Compressor DC link
Low Voltage
DC charging is not performed at Outdoor unit after starting
relay turn on.
2 4 1 Outdoor unit High Pressure Switch System is turned off by Outdoor unit high pressure switch.
2 5 1 Outdoor unit Input Voltage High/ Low
Voltage Outdoor unit input voltage is over 487V or below 270V
2 6 1 Outdoor unit Inverter Compressor Start
Failure
The First Start Failure by Outdoor unit Inverter
Compressor Abnormality
2 8 1 Outdoor unit Inverter DC link High Voltage System is turned off by Outdoor unit DC Voltage Over
Charging
2 9 1 Outdoor unit Inverter Compressor Over
Current Outdoor unit Inverter Compressor Fault OR Drive Fault
3 0 1
Outdoor unit Constant Speed Compressor2
High Discharge Temperature
System is turned off by Outdoor Uunit Constant Speed
Compressor2 High Discharge Temperature
3 2 1
Outdoor unit Inverter Compressor High
Discharge Temperature
System is turned off by Outdoor unit Inverter Compressor
High Discharge Temperature
3 3 1
Outdoor unit Constant Speed Compressor1
High Discharge Temperature
System is turned off by Outdoor Uunit Constant Speed
Compressor1 High Discharge Temperature
3 4 1 High Pressure of Outdoor Unit System is turned off by excessive increase of high pressure
of Outdoor unit
3 5 1 Low Pressure of Outdoor unit System is turned off by excessive decrease of low pressure
of Outdoor unit
3 6 1 Outdoor unit Low Condensing Ratio Limited Outdoor unit stayed under low condensing limit for 3 minutes
4 0 1
Outdoor unit Inverter Compressor CT
Sensor Fault Outdoor unit Inverter Compressor CT Sensor open or short
4 1 1
Outdoor unit Inverter Compressor
Discharge Temperature Sensor Fault
Outdoor unit Inverter Compressor Discharge Temperature
Sensor open or short
4 2 1 Outdoor unit Low Pressure Sensor Fault Outdoor unit Low Pressure Sensor open or short
4 3 1 Outdoor unit High Pressure Sensor Fault Outdoor unit High Pressure Sensor open or short
4 4 1 Outdoor unit Air Temperature Sensor Fault Outdoor unit Air Temperature Sensor open or short
4 5 1
Outdoor unit Heat Exchanger Temperature
Sensor (Front side) Fault
Outdoor unit Heat Exchanger Temperature Sensor(Front
side) open or short
4 6 1
Outdoor unit Suction Temperature Sensor
Fault Outdoor unit Suction Temperature Sensor open or short
[Error Code (Outdoor Unit)]
• This page is about outdoor error code. It can vary depending on outdoor unit. For more information, please
refer to the outdoor unit manual.

Troubleshooting
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Display Title Cause of Error
Outdoor unit related error
4 7 1
Outdoor unit Constant Speed Compressor1 Discharge
Temperature Sensor Fault
Outdoor unit Constant Speed Compressor1 Discharge
Temperature Sensor open or short
4 8 1
Outdoor unit Constant Speed Compressor2 Discharge
Temperature Sensor Fault
Outdoor unit Constant Speed Compressor 2 Discharge
Temperature Sensor open or short
4 9 1 Outdoor unit Faulty IPM Temperature
Sensor Outdoor unit IPM Temperature Sensor short/open
5 0 1
Omitting connection of R, S, T power of
Outdoor unit Omitting connection of outdoor unit
5 1 1
Excessive capacity of indoor units Excessive connection of indoor units compared to capacity
of Outdoor Unit
5 2 1
Transmission error : inverter PCB ’ Main
PCB
Failing to receive inverter signal at main PCB of Outdoor
unit
5 3 1
Transmission error : indoor unit ’ main
PCB of Outdoor Unit
Failing to receive indoor unit signal at main PCB of
Outdoor Unit .
5 4 1
Reverse connection of R, S, T power of
Outdoor unit
Reverse connection or omitting connection of R, S, T power
of Outdoor unit
5 7 1
Outdoor unit Communication Error with
Inverter Controller
Outdoor unit Controller part cannot receive inverter control
signals (usually happens after on-boarding)
6 0 1
Inverter PCB EEPROM Error of Outdoor
Unit Access Error of Inverter PCB of Outdoor unit
6 7 1 Outdoor unit Fan Lock Restriction of Outdoor unit
6 9 1 Constant1 CT Sensor Error of Outdoor Unit Constant1 CT Sensor open or short of Outdoor unit
7 0 1 Constant2 CT Sensor Error of Outdoor Unit Constant2 CT Sensor open or short of Outdoor unit
7 3 1
Instant Over Current(Peak) of Outdoor unit
PFC Instant Over Current(Peak) of Outdoor unit PFC
7 5 1 Outdoor unit Fan CT Sensor Error Outdoor unit Fan CT Sensor open or short
7 6 1
Outdoor unit Fan DC Link High Voltage
Error Outdoor unit Fan DC Link High Voltage Error
7 7 1 Outdoor unit Fan Over Current Error Outdoor unit Fan Current is over 5A
7 9 1 Outdoor unit Fan Start Failure Error Outdoor unit Fan First Position Sensing Failure
8 6 1 Outdoor unit Main PCB EEPROM Error Communication Fail Between Outdoor unit Main MICOM
and EEPROM or omitting EEPROM
8 7 1 Outdoor unit Fan PCB EEPROM Error Communication Fail Between Outdoor unit Fan MICOM and
EEPROM or omitting EEPROM
[Error Code (Outdoor Unit)]
• This page is about outdoor error code. It can vary depending on outdoor unit. For more information, please
refer to the outdoor unit manual.

Troubleshooting
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Display Title Cause of Error
Outdoor unit related error
1 0 4 1 Communication Error Between
Outdoor unit and Other Outdoor Unit
Failing to receive Slave Unit signal at main PCB
of Outdoor unit
1 0 5 1 Outdoor unit Fan PCB
Communication Error
Failing to receive fan signal at main PCB of
master unit.
1 0 6 1 Outdoor unit FAN IPM Fault Error Instant Over Current at Outdoor unit Fan IPM
1 0 7 1 Outdoor unit Fan DC Link Low
Voltage Error
Outdoor unit Fan DC Link Input Voltage is under
380V
1 1 3 1 Outdoor unit Liquid pipe Temperature
Sensor Error
Liquid pipe temperature sensor of Outdoor unit is
open or short
1 1 5 1 Outdoor unit Subcooling Outlet
Temperature Sensor Error
Outdoor unit Subcooling Outlet Temperature
Sensor open or short
1 5 1 1 Failure of operation mode conversion
at Outdoor Unit Pressure unbalance between Outdoor Units
1 7 3 1 Outdoor unit Constant Speed
Compressor Fault
Comp locking, Check Valve leakage, comp
dielectric break down at Outdoor Unit
1 7 4 1 Outdoor unit rated speed 2
condenser over-current
Outdoor unit rated speed 2 condenser burned /
locked or fault by over-current
1 9 0 1 Excessive increase of outdoor unit
Inverter PCB Heat sink Temperature
Outdoor unit Inverter PCB Heat sink temperature
is over 95℃
1 9 1 1 Outdoor unit Inverter PCB Heat sink
Temperature sensor error
Outdoor unit Inverter PCB Heat sink temperature
sensor open or short
1 9 3 1
Excessive increase of Outdoor unit Fan
PCB Heat Sink Temperature
Outdoor unit Fan Inverter PCB Temperature is Over
95°C
1 9 4 1
Outdoor unit Fan PCB Heat Sink
Temperature Sensor Error
Outdoor unit Fan PCB Heat Sink Temperature Sensor
open or short
[Error Code (Outdoor Unit)]
• This page is about outdoor error code. It can vary depending on outdoor unit. For more information, please
refer to the outdoor unit manual.