Refrigeration cycle

The complete circulation of refrigerant through an air conditioning system as it changes temperature and pressure, i.e., changes its state from vapor to liquid, then back to vapor. Air-conditioning refrigerant in vapor form is pressurized in the compressor, air-cooled in the condenser, and becomes a liquid which passes through the receiver-drier into the expansion valve where it expands into low-pressure liquid. It then flows through the evaporator where it expands again and starts to boil, absorbing heat from the core and cooling the air going into the passenger compartment. The compressor draws off the low-pressure vaporized refrigerant and recycles it.