Model reference
LG ARNUSERIES
Air Conditioner
4 documents155 error codes23 service modes
Available documentation
Service Manual
- Air Conditioner Service Manual - ARUV/ARUN Series338 pg
- Air Conditioner Service Manual R410A338 pg
- Air Conditioner Service Manual354 pg
- Air Conditioner Service Manual R410A354 pg
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Error codes (155)
CodeMeaning
01Indoor unit room temperature sensor is open or short circuit.02Indoor unit inlet pipe temperature sensor is open or short circuit.03Communication error between wired remote controller and indoor unit; indoor…04Malfunction of drain pump; condensed water level rises and float switch detects…05Communication error between outdoor unit and indoor unit; indoor unit PCB fails…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; serial number on EEPROM is 0 or FFFFFF.10Poor indoor fan motor operation; disconnected fan motor connector or indoor fan…100Excessive rise of discharge temperature of constant speed compressor 1 of sub1…101Excessive rise of discharge temperature of constant speed compressor 2 of sub1…102Excessive rise of discharge temperature of constant speed compressor 1 of sub2…103Excessive rise of discharge temperature of constant speed compressor 2 of sub2…104Communication error from sub1 outdoor unit to main outdoor unit; failing to…105Communication error from fan PCB to main PCB; failing to receive fan signal at…106Over-current of main outdoor fan motor (fan IPM fault).107Low voltage in main outdoor fan motor driver.108Communication error from main PCB to fan PCB; failing to receive main signal at…109High pressure switch of sub1 outdoor unit operated due to high pressure rising.11Outdoor unit cannot recognize the indoor unit; addressing signal does not come…110Reverse connection or omitting connection of R, S, T power of sub1 outdoor unit.111Communication error from main outdoor unit to sub1 outdoor unit; failing to…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 155 error codes
122Discharge temperature sensor of constant speed compressor 2 of sub1 outdoor…123Temperature sensor of front-side heat exchanger of sub1 outdoor unit is open or…124Temperature sensor of rear-side heat exchanger of sub1 outdoor unit is open or…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 outdoor unit is open or…136Temperature sensor of rear-side heat exchanger of sub2 outdoor unit is open or…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 due to high pressure rising.141Reverse connection or omitting connection of R, S, T power of sub2 outdoor unit.142Communication error from main outdoor unit to sub2 outdoor unit; failing to…143High pressure of sub1 outdoor unit; system off by excessive increase of high…144Low pressure of sub1 outdoor unit; system off by excessive decrease of low…145High pressure of sub2 outdoor unit; system off by excessive increase of high…146Low pressure of sub2 outdoor unit; system off by excessive decrease of low…147Low or high voltage of sub1 outdoor unit; input voltage more than 487V or less…148Voltage detection circuit of sub1 outdoor unit is out of order.149Low or high voltage of sub2 outdoor unit; input voltage more than 487V or less…150Voltage detection circuit of sub2 outdoor unit is out of order.151Outdoor 4-way (reversing) valve switching error; pressure unbalance between…152System off due to excessive discharge temperature of constant speed compressor…153System off due to excessive discharge temperature of constant speed compressor…154High pressure switch of sub3 outdoor unit operated due to excessive high…155Reverse connection or omitting connection of R, S, T power of sub3 outdoor unit.156Transmission error157High pressure sensor of sub3 outdoor unit is open or short.158Low pressure sensor of sub3 outdoor unit is open or short.159Air temperature sensor of sub3 outdoor unit is open or short.161Compressor suction temperature sensor of sub3 outdoor unit is open or short.162Discharge temperature sensor of constant speed compressor 1 of sub3 outdoor…163Discharge temperature sensor of constant speed compressor 2 of sub3 outdoor…164Temperature sensor of front-side heat exchanger of sub3 unit is open or short.165Temperature sensor of rear-side heat exchanger of sub3 unit is open or short.166Liquid pipe temperature sensor of sub3 outdoor unit is open or short.167Subcooling inlet temperature sensor of sub3 outdoor unit is open or short.168Subcooling outlet temperature sensor of sub3 outdoor unit is open or short.169System off by excessive increase of high pressure of sub3 outdoor unit.170System off by excessive decrease of low pressure of sub3 outdoor unit.171Input voltage of sub3 outdoor unit exceeds tolerable range.172Voltage detection circuit of sub3 outdoor unit is out of order (sensor open or…173Failure of main constant speed compressor operation; compressor locking, check…174Failure of sub1 constant speed compressor 1 operation; compressor locking…175Failure of sub1 constant speed compressor 2 operation; compressor locking…176Failure of sub2 constant speed compressor 1 operation; compressor locking…177Failure of sub2 constant speed compressor 2 operation; compressor locking…178Failure of sub3 constant speed compressor 1 operation; compressor locking…179Failure of sub3 constant speed compressor 2 operation; compressor locking…200Pipe detection error201HR unit 1 liquid pipe temperature sensor is open or short.202HR unit 1 sub-cooling inlet pipe temperature sensor is open or short.203HR unit 1 sub-cooling discharge pipe temperature sensor is open or short.204Transmission error between HR unit 1 and outdoor unit.205HR unit 2 liquid pipe temperature sensor is open or short.206HR unit 2 sub-cooling inlet temperature sensor is open or short.207HR unit 2 sub-cooling outlet temperature sensor is open or short.208Transmission error between HR unit 2 and outdoor unit.209HR unit 3 liquid pipe temperature sensor is open or short.21DC peak / IPM fault or overcurrent to inverter compressor.210HR unit 3 sub-cooling inlet temperature sensor is open or short.211HR unit 3 sub-cooling outlet temperature sensor is open or short.212Transmission error between HR unit 3 and outdoor unit.213HR unit 4 liquid pipe temperature sensor is open or short.214HR unit 4 sub-cooling inlet temperature sensor is open or short.215HR unit 4 sub-cooling outlet temperature sensor is open or short.216Transmission error between HR unit 4 and outdoor unit.217HR unit 5 liquid pipe temperature sensor is open or short.218HR unit 5 sub-cooling inlet temperature sensor is open or short.219HR unit 5 sub-cooling outlet temperature sensor is open or short.22Overcurrent of inverter compressor; current flowing at CT sensing circuit…220Transmission error between HR unit 5 and outdoor unit.221HR unit 6 liquid pipe temperature sensor is open or short.222HR unit 6 sub-cooling inlet temperature sensor is open or short.223HR unit 6 sub-cooling outlet temperature sensor is open or short.224Transmission error between HR unit 6 and outdoor unit.225HR unit 7 liquid pipe temperature sensor is open or short.226HR unit 7 sub-cooling inlet temperature sensor is open or short.227HR unit 7 sub-cooling outlet temperature sensor is open or short.228Transmission error between HR unit 7 and outdoor unit.229HR unit 8 liquid pipe temperature sensor is open or short.23Poor DC voltage charge for driving inverter compressor after starting relay…230HR unit 8 sub-cooling inlet temperature sensor is open or short.231HR unit 8 sub-cooling outlet temperature sensor is open or short.232Transmission error between HR unit 8 and outdoor unit.24High pressure switch of main outdoor unit has tripped; system off due to high…240Central controller CNU connection failure241Central controller data transmission error242Central controller receive error243Central controller receive buffer overflow244Central controller to CNU data transmission failure245Central controller send timeout246Central controller receive timeout25Low or over voltage; input voltage is out of tolerable range.250Central controller checksum error251Central controller receive zero error252Central controller wrong address error32Excessive rise of inverter compressor discharge temperature; system off.33Excessive rise of constant speed compressor discharge temperature on main…34Excessive rise in high pressure of main outdoor unit; system off by high…35Excessive decrease of low pressure of main outdoor unit; system off by low…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 of outdoor unit is open or…46Suction temperature sensor of main outdoor unit is open or short.47Discharge temperature sensor of constant speed compressor of main outdoor unit…48Temperature sensor of rear-side heat exchanger of main outdoor unit is open or…49Voltage detection circuit of main outdoor unit is out of order.51Excessive capacity of indoor units connected compared to outdoor unit capacity…52Communication error from inverter PCB to main PCB; main PCB cannot receive…53Communication error from indoor unit to main PCB of outdoor unit; indoor unit…54Reverse connection or omitting connection of R, S, T power of main outdoor unit…57Communication error from main PCB to inverter PCB; main PCB cannot receive…62Overheat of inverter PCB heat sink; excessive rise of inverter heat sink…65Temperature sensor on heat radiator panel of inverter PCB is open or short.
Service modes (23)
- Auto Addressing (Outdoor Unit)["Ensure all DIP switch settings are properly completed.","Power on all outdoor units, HR units…
- auto_addressing1
- Auto-Addressing1
- Factory Setting Value Display (Main Unit)Power on the main outdoor unit. Factory setting values are automatically displayed in 7-segment on…
- Forced Operation (Cooling Only outdoor model)["Press the forced operation button on the main unit.","Unit operates in cooling mode with setting…
- Forced Operation (Heat Pump outdoor model)["Press the forced operation button on the main unit.","Indoor fan operates at low speed for about…
- Forced Operation (Indoor Unit - Cooling Only Model)Press the forced operation button on the indoor unit.
- Forced Operation (Indoor Unit - Heat Pump Model)Press the forced operation button on the indoor unit
- forced_operationPress the forced operation (power) button on the indoor unit once.
- forced_operation_cooling_onlyPress the forced operation button on the indoor unit.
- forced_operation_heat_pumpPress the forced operation button on the indoor unit.
- initial_setup1. Complete all DIP switch settings before powering on. 2. Apply power
- initial_setup_factory_displayApply power to outdoor unit. Factory setting values are automatically displayed on 7-segment for 24…
- Instant Indoor Unit Checking Mode - Cooling1. Set main outdoor unit DIP switch SW03M
- Instant Indoor Unit Checking Mode - Heating1. Set main outdoor unit DIP switch SW03M
- Instant Indoor Unit Checking Mode (Outdoor Unit)["Set DIP switch on outdoor main PCB
- instant_indoor_unit_checking1
- instant_indoor_unit_checking_coolingSet main outdoor unit DIP switch SW03M position 1 ON (cooling)
- instant_indoor_unit_checking_heatingSet main outdoor unit DIP switch SW03M positions 1 and 2 ON (heating)
- Test Operation (Indoor Unit - Wall Mounted/Art Cool)1
- Test Operation (Wall Mounted / Art Cool indoor units)["Supply power to the unit.","Press and hold the ON/OFF button on the indoor unit for 3-5…
- test_operationPress and hold ON/OFF button on indoor unit for 3-5 seconds until buzzer sounds 1 beep.
- test_operation_art_cool_wall_mounted1
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