Alongside is a simplified animation of the vapour compression refrigeration process which common to most refrigeration systems.   In response to a sensor (usually temperature) the process begins.     Refrigerant vapour in the COMPRESSOR is compressed, causing a rise in it's temperature approximately 10 degrees celsius above outside ambient. The High-pressure High-temperature vapour flows into the  CONDENSER. The refrigerant vapour, being hotter than it's surroundings gives up it's heat . The vapour condenses and becomes a liquid.  Liquid refrigerant is stored in the RECEIVER as a reservoir before being metered into the evaporator by a flow expansion device.  The refrigerant liquid expands resulting in a fall in temperature to approximately 10 degrees celsius below process requirements, and flows into  The EVAPORATOR. Here the low temperature liquid absorbs heat from the surroundings and evaporates (boils) becoming a liquid-vapour mixture at low temperature, evaporating totally before returning to the COMPRESSOR to begin the cycle again.

 

This is the most common method used in the refrigeration systems process. You will find it in use in applications from giant refrigerated storage facilities to food display counters in the your local deli; from air conditioning NASA Mission Control Centre to a high street shop. There's a good chance that your domestic refrigerator runs it this way too.