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Error code reference
LG Heat Pump Error Codes
74 error codes documented with diagnostic procedures.
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01Indoor unit air sensor (room temperature sensor) open or short circuit.02Indoor unit inlet pipe sensor open or short circuit detected.03Wired remote controller to indoor unit transmission error04Drain pump malfunction05Outdoor unit to indoor unit transmission error06Indoor unit outlet pipe sensor open or short circuit detected.07Indoor unit is operating in a different mode than other connected indoor units (e.g…09Serial number error21DC peak22Max CT23DC link24High pressure25Low/over voltage32Inverter compressor discharge temperature33Constant speed compressor discharge temperature34High pressure35Low pressure40CT sensor open or short circuit.41Inverter compressor discharge pipe sensor (discharge temperature) open or short.42Low pressure sensor open or short circuit.43High pressure sensor open or short circuit.44Outdoor unit air sensor open or short circuit.45Outdoor unit pipe sensor (left) open or short circuit.46Suction pipe sensor open or short circuit.47Normal (constant speed) compressor discharge pipe sensor open or short circuit.48Outdoor unit pipe sensor (right) open or short circuit.49Voltage sensor open or short circuit.51Indoor connection over capacity52Transmission error from inverter PCB to main PCB in outdoor unit53Transmission error from indoor unit to main PCB in outdoor unit54Reverse connection or disconnection of R,S,T power line (CRUN1008T1 only).55Transmission error from central controller to main PCB in outdoor unit56Transmission error from main PCB in outdoor unit to central controller57Transmission error from main PCB to inverter PCB in outdoor unitCH01Problem in Remote Room Air sensor (open/short/disconnected).CH02Problem in Refrigerant (Inlet side) sensor.CH03Bad communication between control panel and indoor unit.CH05Bad communication between Indoor unit and Outdoor unit.CH06Problem in Refrigerant (Outlet side) sensor.CH08Problem in Water Tank sensor.CH09PCB Program (EEPROM) Fault due to electrical or mechanical damage.CH13Problem in Solar-thermal sensor.CH14Problem in Flow Switch (open while water pump running, or closed while pump not running).CH15Water pipe overheated (leaving water temperature above 72°C).CH16Problems in sensors (general sensor fault).CH17Problem in Water-inlet sensor.CH18Problem in Water-outlet sensor.CH19Problem in Water-interlim sensor.CH21DC Peak (IPM Fault)CH22Max CT (over current detected by current transformer).CH23DC Link voltage is low (1phCH24High Pressure / Low Pressure switch activated.CH25Input voltage is too low or too high.CH26Problem in DC Compressor positioning (position detect error).CH27PSC/PFC FaultCH28DC Link voltage is high.CH29High current at compressor phases (inverter compressor input current over 30A).CH32Temperature at discharge pipe is too high (105°C or above).CH39Transmission error between PFC Micom and INV Micom.CH40Problem in CT (current transformer) sensorCH41Problem in discharge-pipe temperature sensor (inverter side).CH44Problem in ambient temperature sensor.CH45Problem in condenser-pipe temperature sensor.CH46Problem in suction-pipe temperature sensor.CH51Over capacity combinationCH52Bad communication between internal PCBs (Inverter PCB to Main PCB).CH53Bad communication between Indoor unit and Outdoor unit (outdoor-side code for CH05).CH60EEPROM Checksum mismatched.CH61Temperature at condenser-pipe is too high (65°C).CH62Temperature at heatsink is too high (85°C).CH63Temperature at condenser-pipe is too low.CH65Problem in heatsink temperature sensor (short if ≥130°C, open if < -30°C).CH67BLDC motor fan lock (outdoor)CH73AC input instant over current error
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