*The vapour compression refrigeration system is by far the most popular and widely used system in refrigeration and air conditioning both for industrial and domestic applications.
*In this system the working substance is a refrigerant like NH3, R-11, R-12, ctc.
*A refrigerant readily evaporates and condenses depending upon the pressures and temperatures during the cycle. Therefore, refrigerant undergoes a change of phase alternately between liquid and vapour phases without leaving the system.
*During evaporation, it absorbs latent heat from the brine or cold chamber and during the process liquid changes into vapour, hence, creates cooling effect in the cold chamber.
*During condensation, refrigerant rejects heat to external system like cooling water or to the atmosphere and the refrigerant itself converts from vapour to liquid.
*The system mainly consists of a refrigerant, compressor, a liquid receiver, a refrigerant control valve also called as expansion valve and evaporator.
