So funktionieren Klimaanlagen

How Air Conditioners Work

In principle, air conditioning systems work by transporting and delivering energy from one location to another. When an air conditioner is cooling, heat is withdrawn from the air in a room and transported outside and released through the so called condenser and refrigerant cycle.

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Cooling Operation

  • The gaseous refrigerant is drawn in by a compressor and is then compressed until the temperature becomes very high.
  • The now hot but still gaseous refrigerant is then pumped from the compressor to the so called capacitor or condenser, where a fan cools down the refrigerant with help of the outside air, allowing it to condense and return to a liquid state.
  • The liquid refrigerant, still under great pressure, is sent back into the evaporator (in the indoor unit) via the expansion valve.


  • The warm air in the room is drawn in with the help of a fan and then blown across the evaporator. The now cooled down air (= heat removed air) is returned back into the room. It is here that the actual "cooling" ? or rather "heat removal" occurs. When the liquid refrigerant evaporates, the required energy (heat) is removed from the warm air in the room.
  • The evaporated and thereby again gaseous refrigerant is routed through the cooling cycle and into the compressor, where it is compressed again.


Heating Operation

In the heating operation the cooling cycle is reversed; here the heat is withdrawn from the warm air outside and released into the room by the indoor unit.

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