Anti-freezing control method and device for air conditioner heat exchanger

The invention discloses an anti-freezing control method for an air conditioner heat exchanger. The control method comprises the steps of acquiring an pipe temperature T1 of an indoor heat exchanger; determining a preset temperature region where the pipe temperature T1 of the indoor heat exchanger is located and a time threshold value N1 corresponding to the temperature region; recording the accumulated time t1 when the pipe temperature of the indoor heat exchanger is continuously positioned in the determined temperature region; if the determined accumulated time t1 is longer than or equal to the time threshold value N, controlling an outdoor unit of an air conditioner to stop running and an indoor unit to enter a defrosting mode. The invention also discloses an anti-freezing control device for the air conditioner heat exchanger. The low-temperature refrigeration effect of the common air conditioner can be achieved without a low-temperature refrigeration device, and a refrigeration demand for extremely low temperature of an outdoor environment is met; furthermore, multiple conditions for entering the defrosting mode are set, and each condition corresponds to different defrosting parameters, so that high-efficiency defrosting can be realized, and resources are effectively used.