Hermetic refrigerator compressor, the black sealed unit at the back bottom of a fridge

Refrigerator inverter compressor board: what is safe to check

Inverter boards make variable-frequency 3-phase power for the compressor. Electrical checks of the board and compressor terminals are allowed; anything that opens the sealed refrigerant system is EPA 608 work and blocked. Boards fail more often than compressors.

Cross-checked ~45 min advancedBrands: LG, Samsung, Whirlpool, GE

Before you start

Inverter boards store high DC voltage in their capacitors; wait several minutes after unplugging and verify the DC bus is near 0 V
Live-voltage tests: use a CAT III-rated meter, insulated probes and one hand; keep the other hand away from the chassis
Do not touch compressor terminals with power on
Sealed system (compressor replacement, recharge, brazing, leak repair): blocked. Refer to an EPA 608-certified technician

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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