Air Conditioning Function Switch

Air Conditioning Function Switch

When AC, DEM or Re-circulation 1→ is selected the system engages the Air conditioning compressor using the electromagnetic clutch. The in-car temperature is automatically corrected to the pre selected level by the system sensors.

When MAN (manual mode) is selected it provides the operator selection of fan speed and in-car temperature selection facilities. The in-car temperature is not thermostatically corrected to a predetermined level by the system sensors.

When ECO is selected the system is in economy mode which allows the fan speed and heating levels to be selected but gives no cooling. The air conditioning compressor is not engaged putting a minimum load on the engine.

When manual re-circulation is selected the blower flaps are closed and only that air which is in the vehicle is re-circulated. When the ignition is turned off the blower flaps revert to the fresh air position.

Refrigeration Cycle

The Compressor draws low pressure refrigerant from the evaporator and by compression, raises refrigerant temperature and pressure. High pressure, hot vapourised refrigerant enters the Condenser where it is cooled by the flow of ambient air. A change of state occurs as the refrigerant cools in the condenser and it becomes a reduced temperature high pressure liquid.

1. Compressor
2. Condenser
3. Receiver-Drier
4. Expansion Valve
5. Evaporator
6. Triple Pressure Switch (Trinary switch)