Error code reference

LG Air Conditioner Error Code 4

Temperature of heat sink (power module) has exceeded 95°C, causing overheating protection.

SourceLG HPWI Series Air Conditioner - Service Manual (25/35 Models)p. 50

Diagnostic procedure

The full 4 procedure

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MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Compressor will restart when heat sink thermistor temperature drops below 85°C; check for adequate airflow around outdoor unit and heat sink condition.

SourceLG HPWI Series Air Conditioner - Service Manual (25/35 Models)p. 50

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Where this code is documented

13 manuals in the MyPros+ library document this code for LG air conditioner.

Models covered by the manuals that document this code

More models are covered than are listed here.

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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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