Air conditioning system (Audi A4 B5)

Here, just like in a home refrigerator, a compressor compresses a gaseous refrigerant. The compressor is driven by a poly V-belt from the engine crankshaft. When compressed, the refrigerant liquefies and enters the evaporator near the dashboard. It looks like a radiator. In it, the refrigerant evaporates and can absorb heat. The air passing through the evaporator enters the passenger compartment already cooled. Through the condenser next to the cooling radiator in the engine compartment, the refrigerant again enters the compressor. To enhance condensation, the radiator fan runs constantly.

The climate control system is a complex system, in which you can do something yourself only to a limited extent. Therefore, it is not described here.

Belt drives, including the poly V-belt for the climate control system, are described in the section Generator.

(Information obtained from this resource audimanual.ru)