





Based on customer reports and repair data, this part commonly fixes these issues:
As the outdoor temperatures get colder, the outdoor coils can start to freeze up more often. When the coils frost up, a defrost control board or thermostat will energize a reversing valve to divert the warmer refrigerant from the indoor coil to help melt the excess frost from the outdoor coil. If the defrost control board is defective, the frost on the outdoor coils may be unable to melt. Before replacing the defrost control board, first confirm the reversing valve and defrost thermostat are functioning. If the reversing valve and defrost thermostat are working properly, the defrost control board is likely defective.