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Air Conditioning

GLL1034165Courtesy of VOLVO CARS CORPORATION
GLL1035305Courtesy of VOLVO CARS CORPORATION
  1. Compressor, swept volume 160 cm3
  2. Condenser
  3. Drier (integrated)
  4. Pressure sensor
  5. Service valves
  6. Heat exchanger
  7. Thermal expansion valve (TXV)
  8. Evaporator

The air conditioning only operates in outside temperatures above 0 °C. In lower temperatures, the pressure in the system becomes too low and the compressor is not engaged. The reason for this is to prevent the moisture on the surface of the evaporator from freezing to ice and building up, which may impede function or damage the evaporator.

The air conditioning only operates when the engine is running. It operates regardless of engine speed and vehicle speed. However, the compressor is disengaged for full acceleration, kickdown, in order to provide enhanced output for acceleration during overtaking, for example. The output of the air conditioning is regulated via the compressor's swept volume as well as via the climate unit's fan.

The blower fan must be operating before the climate control system can be engaged.

The evaporator (8) receives the liquid refrigerant. The drier (3) is integrated into the condenser. The compressor (1) is a pump that pressurizes the refrigerant. The heat transfer takes place in the condenser (2). The expansion valve (7) regulates the flow of refrigerant to the evaporator.