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Frequently asked questions about cars and motorcycles

How does the air conditioning system of the Mercedes A-Class work?

Model: Mercedes Classe A W176 - Years 2012-2018
Part: Air conditioner

Let's see how the air conditioning system works on a Mercedes Classe A: it is a closed system whose key components are: the compressor, which is activated by a belt connected to the engine, which compresses a refrigerant gas; a condenser, which is a small radiator located in front of the engine radiator, where the hot and compressed refrigerant gas releases its heat to the outside air, condensing and becoming a high-pressure liquid. The expansion valve is a narrow passage where the refrigerant is expanded, causing a sudden cooling of the refrigerant, and then it passes into the evaporator, another small radiator hidden in the dashboard: the hot air from the cabin is passed through the cold evaporator. The refrigerant absorbs the heat from the air, cooling it down. The moisture in the air condenses on the evaporator and is drained outside: this is why air conditioning dehumidifies and defrosts the glass. The continuous cycle is: compression/condensation/expansion/evaporation/return, and the cycle starts over again.

Posted on 26 August 2025 by ScegliAuto

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