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Sonntag, 3. März 2024

How does a car's air conditioning system work?

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The air conditioning system in a car works like a refrigerator. The key technological element is the compressor. It circulates the refrigerant. With the aid of the refrigerant, the air from the vehicle interior is cooled.

What happens to the refrigerant in the cycle?

The warm air from the interior is first fed to the evaporator (1). Here the cold, liquid refrigerant takes the heat from the air and becomes gaseous – the refrigerant evaporates. The cooler air is fed back into the car's interior.

The compressor (2) draws in the now gaseous refrigerant. Here it is compressed and compacted like in an air pump. This makes it hot.

Then, the hot vapor arrives at the condenser (3): A fan ensures that cold exterior air flows around the hot refrigerant, cooling it and allowing it to discharge heat to the exterior air. This makes it liquid again.

Now the refrigerant flows through an expansion valve (4). Similar to a valve of an aerosol can, the refrigerant is fed into the evaporator as a mix of vapor and liquid. Its pressure has dropped and it can once again absorb heat from the vehicle interior. The cycle begins anew.

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Visit for further information about maintenance of air conditioning systems.