The refrigeration cycle or heat pump cycle is the model describing the transfer of heat from AREA of lower temperature to AREA of higher temperature. It defines the operating principles behind refrigerators, air conditioners, heaters, and other "heat pumping" devices.
PHASE 1 in the phase after the refrigerant passes through an evaporator (D), where warm air heats the fluid and converts it completely to vapor.
PHASE 2 in the phase after the fluid passes through a compressor (A) which increases the fluid's pressure and temperature up to super-heated levels.
PHASE 3 and 4 are when the fluid passes through an Condenser (B), which transfers heat to the ambient (Release the heat to outside) and condenses the fluid to liquid.
PHASE 5 is the state after the fluid passes through an expansion valve or metering device (C), which lowers the pressure of the fluid. This cools the fluid and subsequently turns the liquid into a liquid/vapor mixture.
