LG AMNH076LQL0 User manual

LG
Multi Type Air Conditioner
SERVICE MANUAL
LG
CAUTION
website http://www.lgservice.com
e-mail http://lgservice.com/techsup.html
• BEFORE SERVICING THE UNIT, READ THE SAFETY
PRECAUTIONS IN THIS MANUAL.
• ONLY FOR AUTHORIZED SERVICE PERSONNEL.
MODEL
• Indoor Unit:
AMNH076LQL0
AMNH096LQL0
AMNH096LRL0
AMNH126LRL0
AMNH186LTL0
AMNH246LTL0
AMNH096AP*1
AMNH126AP*1
AMNH076DZ*0
AMNH096DU*0
AMNH126DU*0
• Outdoor Unit: A2UW146FA0
A2UW146FA1
A2UW186FA0
A3UW186FA0
A3UW246FA0
A4UW246FA0
A4UW306FA0
A6UW406FA0
Room Type
Art Cool Type
Art Cool Deluxe Type
Duct Type 1 Way CST
AMNH096BTG0
AMNH126BTG0
AMNH186BTG0
AMNH096BPA0
AMNH126BPA0
AMNH186BHA0
AMNH246BHA0
AMNH306BGA0
AMNH366BGA0
AMNH096TCC0
AMNH126TCC0
4 Way CST
AMNH126TEC0
AMNH186TEC0
AMNH246TFC0
AMNH306TFC0
AMNH366TDC0
CVT
AMNH096VEA0
AMNH126VEA0
AMNH186VBA0
AMNH246VBA0

Service Manual 159
2. A3UW246FA0, A4UW246FA0
Drier
Th1
Th2
Th3
Solenoid
Valve(1)
LEV-A
LEV-B
LEV-C
Header
Room C
LEV-D
Room D
Room A
Field Pi ing
Liquid Room B
Room C
Room D
Room A
Room B
Field Pi ing
4 room model 4 room model
Gas
Accumulator
Constant
Com ressor
Low Pressure
S/W
Inverter
Com ressor
Solenoid
Valve(2)
Heat
Exchanger
Check
Valve(2)
Check
Valve(1)
Reversing
Valve
Oil
Se erator
OUTDOOR UNIT
Refrigerant Flow
Cooling
Heating
Troubleshooting Guide

160 Multi type Air Conditioner
3. A4UW306FA0
Drier
Th1
Th2
Th3
LEV-A
LEV-B
LEV-C
LEV-D
Header
Room C
Room A
Field Pi ing
Gas Room B
Room D
Room C
Room A
Room B
Room D
Field Pi ing
Liquid
Accumulator
Low Pressure
S/W
Constant
Com ressor Inverter
Com ressor
Solenoid
Valve(1)
Solenoid
Valve(2)
Heat
Exchanger
Reversing
Valve
Check
Valve(2)
Check
Valve(1)
OUTDOOR UNIT
Oil
Se erator
Refrigerant Flow
Cooling
Heating
Troubleshooting Guide

Service Manual 161
4. A6UW406FA0
Drier
Th1Th2
Th3
L.E.V.
Check Valve(1 )
Check Valve(2 )Oil
Seperator
Low Pressure S/W
Receiver
Solenoid Valve(1)
Constant Compressor Inverter
Compressor
Accumulator
Heat Exchanger
Reversing Valve
OUTDOOR UNIT
Field Piping Gas(Ø19.05) Field Piping Liquid (Ø9.52)
Refrigerant Flow
Cooling Heating
Troubleshooting Guide

162 Multi type Air Conditioner
5. BD Unit
Main Gas Piping ( Ø15.88)
Refrigerant Flow
[Indoor Unit]
D Liquid(Ø6.35)
C Liquid(Ø6.35)
B Liquid(Ø6.35)
A Liquid(Ø6.35)
D Liquid(Ø9.52)
C Liquid(Ø9.52 or Ø12.7)
B Liquid(Ø9.52 or Ø12.7)
A Liquid(Ø9.52 or Ø12.7)
Cooling Heating
Main Liquid
Piping ( Ø9.52)
Outdoor Unit
LEV-D LEV-C LEV-B LEV-A
Troubleshooting Guide

Service Manual 163
■Error Indicator
•The function is to self-diagnoisis airconditioner and express the troubles identifically if there is any trouble.
•Error mark is ON/OFF for the operation LED of evaporator body in the same manner as the following table.
•If more than two troubles occur simultaneously, primarily the highest trouble fo error code is expressed.
•After error occurrence, if error is released, error LED is also released simultaneously.
•To operate again on the occurrence of error code, be sure to turn off the power and then turn on.
•Having or not of error code is different from Model.
Troubleshooting Guide
Self-diagnosis Function
Indoor Error
Error code Description INV TPS LED 1
(Red) LED 2 (Green) Indoor Status
00 No Error ON
01 Indoor Room themistor error 1time OFF
02 Indoor in-piping sensor error 2times OFF
03 Remote controller error 3times OFF
04 Drain Pump error 4times OFF
05 Communcation error between in and out 5times OFF
06 Indoor Out-Piping sensor error 6times OFF
07 Differnt mode operation 7times OFF
Outdoor Error
Error Code Description INV TPS LED 1
(Red) LED 2 (Green) Indoor Status
21 DC Peak (IPM Fault) 2times 1time OFF
22 CT 2(Max CT) 2times 2times OFF
23 DC Link Low Volt. 2times 3times OFF
24 L_P/Heater Sink 2times 4times OFF
25 Low voltage / Over voltage 2times 5times OFF
26 DC Comp Position Error 2times 6times OFF
27 PSC Fault Error 2times 7times OFF
28 DC Link High Volt 2times 8times OFF
32 D-Pipe High (INV) 3times 2times OFF
33 D-Pipe High (Normal) 3times 3times OFF
40 CT Sensor (Open/Short) 4times OOFF
41 INV. D-PipeTh Error(Open/Short) 4times 1time OFF
44 Outdoor air Th Error(Open/Short) 4times 4times OFF
45 Cond. Pipe Th Error(Open/Short) 4times 5times OFF
46 Suction Pipe Error(Open/Short) 4times 6times OFF
47 Const D-pipe Th Error(Open/Short) 4times 7times OFF
51 Capacity over 5times 1time OFF
53 Signal error (Indoor ↔Outdoor) 5times 3times OFF
60 EEPROM Check Sum Error 6times OOFF
61 Cond. Pipe High 6times 1time OFF
62 Heatsink High 6times 2times OFF
63 Cond. Pipe Low 6times 3times OFF
65 Heatsoml Th error (Open/Short) 6times 5times OFF

164 Multi type Air Conditioner
Troubleshooting Guide
Trouble analysis
1. Check temperature difference between intake and discharge air, and operating current.
All amount of refrigerant leaked out.
Check refrigeration cycle.
Refrigerant leakage
Clog of refrigeration cycle
Defective compressor
Excessive amount of refrigerant
Normal
Notice:
Temperature difference between intake and discharge air depends on room air humidity. When the room air
humidity is relatively higher, temperature difference is smaller. When the room air humidity is relatively lower
temperature difference is larger.
2. Check temperature and pressure of refrigeration cycle.
Notice:
1. The suction pressure is usually 4.5~6.0 kg/cm2G at normal condition.
2. The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with
putty.
Temp. difference : approx. 0°C
Current : less than 80% of
rated current
Temp. difference : approx. 8°C
Current : less than 80% of
rated current
Temp. difference : less than 8°C
Current : near the rated
current
Temp. difference : over 8°C
Temp. Difference
Operating Current
Suction pressure Temperature
(Compared with (Compared with Cause of Trouble Description
the normal value) the normal value)
High Defective compressor Current is low.
Normal Excessive amount of High pressure does not quickly
refrigerant rise at the beginning of operation.
Insufficient amount of Current is low.
Lower Higher refrigerant(Leakage)
Clogging
Higher
Cycle Troubleshooting Guide

Service Manual 165
Troubleshooting Guide
Electronic Parts Troubleshooting Guide
❇Refer to electronic contorol device drawing & schematic diagram.
1. A2UW146FA0, A2UW146FA1, A2UW186FA0, A3UW186FA0
The Product doesn’t operate at all.
Turn off the main power and wait until LED on outdoor PCB is off.
Turn on the main power again.
Does "Beeping" sound is made from the indoor unit?
• Primarily, the operating condi-
tion of Micom is O.K.
• Check CN-DISP1
Check the voltage of power(AC220V/AC240V, 50Hz).
• The voltage of main power.
• The voltage applied to the unit.
• The connecting method of Indoor/Outdoor connecting cable (each color)
• The P.W.B. Ass'y
(Fuse, Noise Filter, Power Transformer, IC01D, IC02D, etc.)
Trouble 1
NO YES
The operation check of the P.C.B. Ass'y
Procedure
1) The input voltage of power trans-
former.
2) The output voltage of power
transformer.
3) IC01D(7812)
4) IC02D(7805)
5) IC01A(KIA7036)
Specification
1) AC230V ± 30V
: Check the rated voltage
2) 14V ± 3V
3) DC12V
4) DC5V
5) The voltage of micom pin 29
: DC4.5V↑
Remedy
1) Replace
power transfomer.
2) Replace
power transfomer.
3) Replace IC01D.
4) Replace IC02D.
5) Replace IC01A.

166 Multi type Air Conditioner
Troubleshooting Guide
Turn on main power.
While the compressor has been stopped, the compressor does not operate
owing to the delaying function for 3 minutes after stopped.
When the compressor stopped Indoor Fan is driven by a low speed.
At this point the wind speed is not controlled by the remote controller.
(When operated in the Sleeping Mode, the wind speed is set to the low speed as force.)
Caused by the remote controller. Caused by other parts except
the remote controller
When the mark ( ) is displayed in LCD
screen, replace battery. Check the contact of CN-DISP 1 connector
When the detect switch (double key) inside the
remote controller door is fault, it is impossible to
operate temperature regulating(▲/▼) and wind
speed selecting.
Check DISP PWB Ass'y
-Voltage between CN1 ➀-➆:DC+5V
Check the Display PWB Ass'y •Check receiver ass'y
Product doesn't operate with the remote controller.
Trouble 2

Service Manual 167
Troubleshooting Guide
Turn on the main power.
When in air circulation mode, compressor/outdoor fan is stopped.
Turn off main power.
Check the electrical wiring diagram of Outdoor side.
Check the open or short of connecting wires between Indoor and Outdoor.
Check the sensor for Indoor temperature is attatched as close as to be effected by the
themperature of Heat Exchange (EVA.)
When the sensor circuit for Indoor temperature and connector are in bad connection or are
not engaged, Compressor/Outdoor fan is stopped.
•Check the related circuit of R02H(12.1K), R01H(1K), R04H(6.2K), R03H(1K), C01H(102),
C02H(102), Micom(pin No. , ).
•Check the Indoor temperature sensor is disconnected or not (about 10K at 25°C).
Check the Relay(RY-PWR, RY-START) for driving Compressor.
•Check the voltage between brown and blue cable of terminal to connect the Outdoor
(About AC220V / 240V).
•Check the related circuit of relay in Outdoor PCB Ass'y.
Operate Cooling Mode by setting the disired temperature of the remote controller is less
than one of the Indoor temperature by 1°C at least.
The Compressor/Outdoor Fan are don't operate
Trouble 3
Check Point
Between Micom(No. 19) and
GND DC 5V DC 0V
DC 12VDC 1V↓
Between IC01M(No. 10) and
GND
Comp. ON Comp. OFF