General overview
Item | Description |
1 | Blower motor Refer to Component Description |
2 | Pollen filter Refer to Component Description |
3 | Evaporator assembly |
4 | Heat exchanger |
5 | Electric booster heater (if equipped) |
6 | Temperature blend door motor |
7 | Air distribution flap, demister vents |
8 | Air distribution door - center vents |
9 | Air distribution door - footwell |
10 | Air intake door |
11 | Air duct, demister vents |
12 | Air passages - center vents |
13 | Air ducts, rear footwell |
Air flow - defroster vents
Item | Description |
1 | Warm air |
2 | Cold air |
Air flow - center vents
Item | Description |
1 | Warm air |
2 | Cold air |
Air flow - footwell
Item | Description |
1 | Warm air |
2 | Cold air |
Two options are available:
Item | Description |
1 | Condenser |
2 | Air conditioning compressor |
3 | Suction accumulator |
4 | Evaporator assembly |
5 | Blower motor |
6 | Evaporator Core Orifice Tube |
7 | Cooling fans |
8 | High - pressure (liquid and warm) |
9 | Low - pressure (liquid and cool) |
10 | Low pressure (gaseous and cold) |
11 | High pressure (gaseous and hot) |
The engine driven refrigerant compressor (2) sucks in gaseous refrigerant from the suction accumulator and compresses it. The temperature of the refrigerant rises to a value between 70 C and 110 C. It passes to the condenser (1) under high pressure.
At this point heat is drawn from the refrigerant by the air being forced past the cooling fins. Because of this heat loss, the refrigerant liquefies and leaves the condenser.
A fixed orifice tube (6), which separates the refrigerant at high pressure from that at low pressure, is located between the condenser and the evaporator (5). This fixed orifice tube slows down the flow of the refrigerant from the compressor, so that pressure builds up in the condenser.
After passing through the fixed orifice tube the liquid refrigerant expands in the circuit to the evaporator, where it becomes gaseous. This causes heat to be extracted from the air coming into the vehicle. The air cools down, and excess moisture contained in it is condensed and is drained off. The refrigerant coming from the evaporator flows into the refrigerant accumulator and is again sucked in by the refrigerant compressor.
The system is protected by a high-pressure limiting switch, in order to prevent damage by excessive pressure (e.g. because of overfilling with refrigerant). If the pressure exceeds the maximum permitted, the high-pressure switch turns off the refrigerant compressor.
The compressor on-off cycle is controlled by the dual pressure switch depending on the pressure in the refrigerant accumulator. The dual pressure switch turns the refrigerant compressor off permanently if the pressure falls below a permitted value (e.g. if there is a leak).