Error code reference

LG HVAC Error Code 4

LA09xHV/LA12xHV/LS902HPV/LS122HPV: ODU PCB heat sink thermistor open, shorted or overheated to 95°C. Other units: IDU condensate pump float switch risen/opened.

SourceLG Ductless HVAC & PTAC - Tech Sheet: Error Codes & Wiring

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Diagnostic procedure

The full 4 procedure

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MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Heat sink thermistor must be 5,600Ω at 38°C/100°F & 20,700Ω at 10°C/50°F. For float switch: check drain pan is empty & pump working; if no pump, ensure blue jumper plug inserted in IDU PCB plug CN_FLOAT.

SourceLG Ductless HVAC & PTAC - Tech Sheet: Error Codes & Wiring

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Where this code is documented

1 manual in the MyPros+ library documents this code for LG hvac.

Models covered by the manuals that document this code

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The full 4 procedure

Where this code is documented

Models covered by the manuals that document this code

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