Haier · Air Conditioner error code

F12Outdoor EEPROM fault

Cross-checked High-voltage / caution

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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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Normal defrost lasts a few minutes, with the outdoor fan off, steam rising and aux heat on. A unit that stays in defrost points to a defrost thermostat/sensor that never opens, a board fault, or a reversing valve that doesn't shift back. Separate normal behaviour from a real fault first.

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