Model reference
LG ARNU18GS3R1
Air Conditioner
1 document152 error codes5 service modes
Available documentation
Service Manual
- Air Conditioner Service Manual R410A338 pg
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Error codes (152)
CodeMeaning
01Indoor unit air temperature sensor is open or short.02Indoor unit inlet pipe temperature sensor is open or short.03Transmission error between wired remote controller and indoor unit; failing to…04Drain pump malfunction; float switch is open due to rising condensate water…05Transmission error between outdoor unit and indoor unit; no signal transmission.06Indoor unit outlet pipe temperature sensor is open or short.07Operation mode between indoor unit and outdoor unit is different.09Indoor unit EEPROM error; serial number marked on EEPROM is 0 or FFFFFF.10Indoor BLDC fan motor feedback signal is absent for 50 seconds; motor lock or…100System off due to excessive increase of discharge temperature of constant speed…101System off due to excessive increase of discharge temperature of constant speed…102System off due to excessive increase of discharge temperature of constant speed…103System off due to excessive increase of discharge temperature of constant speed…104Transmission error between outdoor units; main outdoor unit is not receiving…105Transmission error between outdoor Main PCB and fan Main PCB (fan to outdoor…106Over current of main outdoor fan motor (inverter fan IPM fault).107DC voltage charging failure of inverter fan motor drive; low voltage of main…108Transmission error between main PCB and the Fan PCB (main to fan direction).109High pressure switch of sub1 outdoor unit operated by high pressure rising.11Indoor unit transmission error; indoor unit doesn't receive signal from outdoor…110Reverse connection or omitting connection of R, S, T power of sub1 outdoor unit.111Transmission error; sub1 outdoor unit is not receiving main outdoor unit signal.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 152 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 between outdoor units; sub2 outdoor unit is not receiving…143System off by excessive increase of high pressure of sub1 outdoor unit.144System off by excessive decrease of low pressure of sub1 outdoor unit.145System off by excessive increase of high pressure of sub2 outdoor unit.146System off by excessive decrease of low pressure of sub2 outdoor unit.147Input voltage of sub1 outdoor unit is more than 487V or less than 270V.148Voltage detection circuit of sub1 outdoor unit is out of order.149Input voltage of sub2 outdoor unit is more than 487V or less than 270V.150Voltage detection circuit of sub2 outdoor unit is out of order.151Failure of operation mode conversion; pressure unbalance between outdoor units…152System off due to excessive rise of constant speed compressor 1 discharge…153System off due to excessive rise of constant speed compressor 2 discharge…154High pressure switch of sub3 outdoor unit operated.155Reverse connection or omitting connection of R, S, T power of sub3 outdoor unit.156Transmission error between outdoor units; sub3 not receiving main outdoor unit…157High 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.161Suction 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 (3phase 380V±10% or…172Voltage sensing circuit of sub3 outdoor unit has abnormal sensor measurement.173Abnormal starting of main constant speed compressor; over-increase of…174Abnormal starting of sub1 constant speed compressor 1; over-increase of…175Abnormal starting of sub1 constant speed compressor 2; over-increase of…176Abnormal starting of sub2 constant speed compressor 1; over-increase of…177Abnormal starting of sub2 constant speed compressor 2; over-increase of…200Pipe detection error after auto addressing; number of indoor units detected…201HR 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 pipe temperature sensor is open or short.207HR unit 2 sub-cooling discharge pipe 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.21IPM fault or overcurrent to inverter compressor.210HR unit 3 sub-cooling inlet pipe temperature sensor is open or short.211HR unit 3 sub-cooling discharge pipe 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 pipe temperature sensor is open or short.215HR unit 4 sub-cooling discharge pipe 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 pipe temperature sensor is open or short.219HR unit 5 sub-cooling discharge pipe temperature sensor is open or short.22Overcurrent flows to inverter compressor; CT sensing circuit detects current…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 pipe temperature sensor is open or short.223HR unit 6 sub-cooling discharge pipe 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 pipe temperature sensor is open or short.227HR unit 7 sub-cooling discharge pipe 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.23DC voltage charging failure for inverter compressor driving after starting…230HR unit 8 sub-cooling inlet pipe temperature sensor is open or short.231HR unit 8 sub-cooling discharge pipe temperature sensor is open or short.232Transmission error between HR unit 8 and outdoor unit.24High pressure switch of main outdoor unit activated; system off by high…240Central controller CNU connection failure; transmission failure between central…241Central controller data transmission error (sending error); CNU to central…242Central controller receive error; data length from CNU is longer than data…243Central controller receive buffer overflow; excessive data received.244Central controller to CNU data transmission failure; receiving time exceeds 3…245Central controller send timeout; data sending failure from central controller…246Central controller receive timeout; data receiving failure from CNU within…25Input voltage is out of tolerable range (low or over voltage) at main outdoor…250Central controller check sum error; received check sum differs from calculated…251Central controller receive zero error; length of received data is 0.252Central controller wrong address error; setting address and actual address are…32System off due to rising of inverter compressor discharge temperature at main…33System off due to rising of constant speed compressor discharge temperature at…34System off by excessive increase of high pressure of main outdoor unit; 3…35System off by excessive decrease of low pressure of main outdoor unit; 3…40Current sensor of inverter compressor is open or short; R phase current drops…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.51Excessive capacity of indoor units connected compared to capacity of outdoor…52Transmission error from inverter PCB to main PCB; failing to receive inverter…53Transmission error from indoor unit to main PCB of outdoor unit; main PCB can't…54Reverse connection or omitting connection of R, S, T power of main outdoor unit.57Transmission error from main PCB to inverter PCB; failing to receive main PCB…62Overheat of inverter heatsink.65Temperature sensor of inverter heatsink fan is open or short.
Service modes (5)
- Auto Addressing (Outdoor Unit)["Ensure all DIP switch settings are properly completed.","Power on all outdoor units, HR units…
- 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…
- Instant Indoor Unit Checking Mode (Outdoor Unit)["Set DIP switch on outdoor main PCB
- 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…
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