System Operation: General

To accomplish the transfer of heat, refrigerant is circulated around a sealed system, where it passes through two pressure/temperature regimes. In each of the regimes the refrigerant changes state, during which process maximum heat absorption or dissipation occurs.

The low pressure/temperature regime is from the thermostatic expansion valve, through the evaporator to the compressor. The refrigerant decreases in pressure and temperature at the thermostatic expansion valve, then changes state from a liquid to a vapor in the evaporator to absorb heat.

The high pressure/temperature regime is from the compressor, through the condenser and receiver drier assembly to the thermostatic expansion valve. The refrigerant increases in pressure and temperature as it passes through the compressor, then releases heat and changes state from a vapor to a liquid in the condenser.

Operation of the A/C (air conditioning) system is controlled by the ATC (automatic temperature control) module.

Refer to: Control Components  (Description and Operation).

The A/C system works in conjunction with:

• The air distribution and filtering system.

  Refer to: Air Distribution and Filtering  (Description and Operation).

• The heating and ventilation system.

  Refer to: Heating and Ventilation  (Description and Operation).