Error code reference

LG Heat Pump Error Code CH40

Problem in CT (current transformer) sensor: initial current error or malfunction of current detection circuit (open/short).

SourceLG AH Series Heat Pump - Service Manualp. 61, 75

LG codes LG heat pump codes

Diagnostic procedure

The full CH40 procedure

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MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Check input power (AC 230V); check C01N voltage (should be 4.0Vdc at 25A); check TRANS; replace main PCB if all checks are normal.

SourceLG AH Series Heat Pump - Service Manualp. 61, 75

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More steps, wiring diagram references, and verified part numbers

Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.

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Where this code is documented

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

Models covered by the manuals that document this code

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The full CH40 procedure

Where this code is documented

Models covered by the manuals that document this code

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