The refrigeration circuit consists of four essential elements:
- evaporator
- compressor
- capacitor
- lamination member
through which the refrigerant undergoes changes of state which make possible the transfer of thermal energy.
Evaporator the refrigerant fluid extracts heat (to 
fluid of the external environment in heat pump mode, to the fluid environment to be conditioned in chiller mode); passing from the evaporator to compressor the refrigerant receives an additional intake of energy in the form of pressure and temperature.
Upon arrival of the refrigerant at capacitor the refrigerant undergoes a change of state giving its heat (fluid in the external environment in chiller mode, the fluid environment to be conditioned in heat pump mode).
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