1. Throttling and depressurization

Throttling and depressurizing the high-temperature and high-pressure liquid refrigerant condensed by the condenser to become a low temperature and low pressure vapor liquid mixture that is easy to evaporate, entering the evaporator for evaporation and absorbing external heat;

2. Regulate flow

The expansion valve can automatically adjust the refrigerant flow into the evaporator according to the temperature signal obtained by the temperature sensor or the head of the air box to meet the needs of changing refrigeration load.

3. Maintain a certain degree of superheat to prevent liquid slugging and abnormal overheating. The expansion valve makes the evaporator have a certain degree of superheat by regulating the flow, ensuring the effective use of the total volume of the evaporator, and avoiding liquid slugging caused by liquid refrigerant entering the compressor; At the same time, the superheat can be controlled within a certain range to prevent abnormal overheating.