METHOD AND DEVICE FOR DEFROSTING EVAPORATOR RELATING TO FOR AIR CONDITIONING UNIT Russian patent published in 2017 - IPC F25B47/02 F25D21/06 F24F12/00 

FIELD: ventilation.

SUBSTANCE: air conditioning unit includes an adjustable heat recovery device. The heat pump includes a refrigerant circulation system with a refrigerant, as well as at least one compressor, at least one condenser, at least one first expansion valve, and at least one evaporator. Further, said heat pump includes at least one four-way valve positioned downstream after compressor and upstream before condenser, said four-way valve is designed to change the direction refrigerant flow in refrigerant circulation system, whereby the refrigerant is sent to the evaporator instead of condenser, bypassing the expansion valve. The heat recovery device is designed to regenerate energy from the first air flow and transfer it to a second air flow, the evaporator being located in the first air flow downstream of the heat recovery device, and the condenser is located in the second air flow downstream of the heat recovery device. The heat pump includes a reservoir and a second expansion valve that are disposed between the first expansion valve and the condenser, the first expansion valve controls the refrigerant flow through evaporator and the second expansion valve regulating the level of refrigerant in the reservoir in cooperation with the first expansion valve in order to obtain an adjustable amount of refrigerant and balanced backpressure in condenser with incomplete compressor load. The method for defrosting evaporator is characterized in that when the frost forms in the evaporator, the temperature of refrigerant passing through the evaporator is increased. At the same time, the heat recovery device is adjusted downward, whereby the evaporator is simultaneously heated both from the inside by raising the temperature of refrigerant and externally by the first air flow, the temperature of which increases when the heat recovery decreases, and thus the evaporator is defrosted.

EFFECT: decreasing the defrosting time of evaporator.

8 cl, 3 dwg