Model reference

LG LRNU18GTLA0

Air Conditioner

2 documents92 error codes7 service modes

Available documentation

Service Manual

Air Conditioner Service Manual R22280 pg
Covers this model
Air Conditioner Service Manual R22280 pg
Covers this model

MyPros+ Max

Diagnose your LG LRNU18GTLA0.

Step-by-step diagnostics from the service manual
Test values, resistance specs, and wiring references
Verified part numbers when replacement is needed

Start diagnosing

$29/month · Cancel anytime · Or $9.95 3-day pass

M+

M+ Max·LG Air Conditioner

01 on my LG LRNU18GTLA0

M+

Indoor unit room temperature sensor is

From Service Manual 936241, p.13:

1.Access service mode to confirm the active fault code and read stored error history.

2.Disconnect the sensor and measure resistance. Expected: 10 kΩ to 12 kΩ at 77°F (25°C).

3.Check the sensor harness for opens. A reading outside 5 kΩ to 50 kΩ indicates a failed sensor.

Part 6322FR2046G

Temperature thermistor

Error codes (92)

CodeMeaning

01Indoor unit room temperature sensor is open or short circuit.02Indoor unit inlet pipe temperature sensor is open or short circuit.03Transmission error between wired remote controller and indoor unit 04Drain pump malfunction 05Transmission error between outdoor unit and indoor unit 06Indoor unit outlet pipe temperature sensor is open or short circuit.07Operation mode between indoor unit and outdoor unit is different (all units…09Indoor unit EEPROM error 10Poor fan motor operation 100Discharge temperature of constant speed compressor 1 of sub1 outdoor unit 101Discharge temperature of constant speed compressor 2 of sub1 outdoor unit 102Discharge temperature of constant speed compressor 1 of sub2 outdoor unit 103Discharge temperature of constant speed compressor 2 of sub2 outdoor unit 104Transmission error from sub1 outdoor unit to main outdoor unit 105Transmission error from fan PCB to main PCB 106Over-current of fan motor (IPM fault).107Low voltage of fan motor driver.108Transmission error from main PCB to fan PCB 109High pressure switch of sub1 outdoor unit operated by high pressure rising.11Transmission error from indoor unit to main PCB of outdoor unit 110Reverse connection or omitting connection of R, S, T power of sub1 outdoor unit.111Transmission error from main outdoor unit to sub1 outdoor unit 113Liquid pipe temperature sensor of main outdoor unit is open or short.114Subcooling inlet temperature sensor of main outdoor unit is open or short.115Subcooling outlet temperature sensor of main outdoor unit is open or short.116High pressure sensor of sub1 outdoor unit is open or short.117Low pressure sensor of sub1 outdoor unit is open or short.118Air temperature sensor of sub1 outdoor unit is open or short.120Suction temperature sensor of sub1 outdoor unit is open or short.121Discharge temperature sensor of constant speed compressor 1 of sub1 outdoor…

View all 92 error codes

122Discharge temperature sensor of constant speed compressor 2 of sub1 outdoor…123Temperature sensor of front-side heat exchanger of sub1 unit is open or short.124Temperature sensor of rear-side heat exchanger of sub1 unit is open or short.125Liquid pipe temperature sensor of sub1 outdoor unit is open or short.126Subcooling inlet temperature sensor of sub1 outdoor unit is open or short.127Subcooling outlet temperature sensor of sub1 outdoor unit is open or short.128High pressure sensor of sub2 outdoor unit is open or short.129Low pressure sensor of sub2 outdoor unit is open or short.130Air temperature sensor of sub2 outdoor unit is open or short.132Suction temperature sensor of sub2 outdoor unit is open or short.133Discharge temperature sensor of constant speed compressor 1 of sub2 outdoor…134Discharge temperature sensor of constant speed compressor 2 of sub2 outdoor…135Temperature sensor of front-side heat exchanger of sub2 unit is open or short.136Temperature sensor of rear-side heat exchanger of sub2 unit is open or short.137Liquid pipe temperature sensor of sub2 outdoor unit is open or short.138Subcooling inlet temperature sensor of sub2 outdoor unit is open or short.139Subcooling outlet temperature sensor of sub2 outdoor unit is open or short.140High pressure switch of sub2 outdoor unit operated by high pressure rising.141Reverse connection or omitting connection of R, S, T power of sub2 outdoor unit.142Transmission error from main outdoor unit to sub2 outdoor unit 143High pressure of sub1 outdoor unit 144Low pressure of sub1 outdoor unit 145High pressure of sub2 outdoor unit 146Low pressure of sub2 outdoor unit 147Low/high voltage of sub1 outdoor unit 148Voltage detection circuit of sub1 outdoor unit is out of order.149Low/high voltage of sub2 outdoor unit 150Voltage detection circuit of sub2 outdoor unit is out of order.151Failure of operation mode conversion 173Failure of main constant speed compressor operation 174Failure of Sub1 constant speed compressor 1 operation 175Failure of Sub1 constant speed compressor 2 operation 176Failure of Sub2 constant speed compressor 1 operation 177Failure of Sub2 constant speed compressor 2 operation 178Failure of Sub3 constant speed compressor 1 operation 179Failure of Sub3 constant speed compressor 2 operation 21DC peak / IPM fault or overcurrent to inverter compressor.22Overcurrent of inverter compressor 23Poor voltage charge for driving inverter compressor 24High pressure switch of main outdoor unit operated 25Low or over voltage 32Discharge temperature of main outdoor unit inverter compressor 33Discharge temperature of main outdoor unit constant speed compressor 34High pressure of main outdoor unit 35Low pressure of main outdoor unit 40Current sensor of inverter compressor is open or short.41Discharge temperature sensor of inverter compressor is open or short.42Low pressure sensor of main outdoor unit is open or short.43High pressure sensor of main outdoor unit is open or short.44Air temperature sensor of main outdoor unit is open or short.45Temperature sensor of front-side heat exchanger is open or short.46Suction temperature sensor of main outdoor unit is open or short.47Discharge temperature sensor of the constant speed compressor of main outdoor…48Temperature sensor of rear-side heat exchanger is open or short.49Outdoor voltage sensing error 51Excessive capacity of indoor units 52Transmission error from inverter PCB to main PCB 53Transmission error from indoor unit to main PCB of outdoor unit 54Reverse connection of R, S, T power of main outdoor unit 57Transmission error from main PCB to inverter PCB 62Overheat of inverter heatsink 65Temperature sensor of fan heatsink is open or short.

Service modes (7)

auto_addressing1
data_display_mode1
forced_operation_cooling_only_modelPress the forced operation button on the indoor unit main body.
forced_operation_heat_pump_modelPress the forced operation button on the indoor unit main body
instant_indoor_unit_checking_cooling1. Set DIP switch
instant_indoor_unit_checking_heating1. Set DIP switches
test_operation_indoorPress and hold ON/OFF button for 3-5 seconds until buzzer sounds 1 beep.

Full entry steps, exit procedures, and test sequences are available in Max.

Related LG air conditioner models

78,000+ service manuals · 160,000+ error codes · 55+ brands

$29/month · Cancel anytime · Or $9.95 3-day pass