Refrigeration is the process of moving heat from one location to another in controlled conditions. The refrigerant is used as the medium which absorbs and removes heat from the space to be cooled.
It works by circulating refrigerant vapor through a system designed to absorb the heat from one area and displace it into another. Refrigerant vapor enters a compressor, where its temperature and pressure are increased, before being routed through a condenser. The vapor in the condenser is cooled by the air around it, turning from a gas into a liquid and thus removing heat from the system when the heat is carried away by the surrounding air.
The liquid refrigerant is then routed through an expansion valve, undergoing an abrupt reduction in pressure which results in the flash evaporation of the refrigerant. This cool refrigerant vapor is then sent through the compressor to once again absorb heat and start the cycle again.