Version Nr. 1-21 - 25.07.2022
Doc. No. 99874020201USL
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5. Functional principle
The cooling unit for enclosures works on the basis of a refrigeration circuit consisting of four main
components: compressor, evaporator, condenser and expansion device.
The circuit is hermetically sealed and R134a refrigerant circulates inside it (R134a is chlorine free and has an
Ozone Destruction Potential [ODP] of 0 and a Global Warming Potential [GWP] of 1430). The compressor
compresses the refrigerant (thus taking it to high pressure and high temperature), and pushes it through the
condenser, where it is cooled by ambient air thus passing from the gas to the liquid state. At the liquid state it
then passes through the capillary pipe being a much lower pressure the refrigerant arrives to the evaporator
where it absorbs the necessary heat to change from liquid to gas state. The gas is then drawn back into the
compressor completing the cycle.
1 Air intake cabinet side 6 Air intake ambient side
2 Radial fan cabinet side 7 Air intake ambient side
3 Evaporator
8 Condenser
4 Air outlet cabinet side 9 Air outlet ambient side
5 Compressor
10 Filter dryer
11 Expansion device