Valeooscope - Air Conditioning System Thermal comfort loop

Operation: The evaporator is a heat exchanger into which the refrigerant fluid is sprayed in order to absorb the heat in the air stream to be cooled. It cannot be dissociated from the expansion valve. The pressure of the refrigerant fluid is reduced by the expansion valve before it enters the evaporator. In the evaporator, heat is exchanged between the cold fluid and the air entering the cabin.

Design: The evaporator is designed according to the volume of the cabin and the specific demands of the applications. The expansion valve and the evaporator form an essential duo in the production of cold in the loop.

Outdoor air

Evaporator

Vaporised liquid

The evaporator

Cabin air

Practical advice:

Heat is exchanged between the outdoor air and the cold surface of the evaporator, air is cooled. A phase change occurs from liquid to gaseous.

The evaporator must be replaced if it is clogged, pierced or contaminated with persistent mould. The most common problems with evaporators are: g Perforation due to corrosion g Fins blocked by soiling or frost g Leaks from the couplings When replacing the evaporator, always replace the receiver drier and the expansion valve/ori- fice tube.

In the course of the heat exchange with the air entering the cabin, the state of the refrigerant gradually changes inside the evaporator. At the evaporator outlet, the change in state is total and the fluid is 100% gaseous.

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