For 1990-2009 cars

The heater ventilation and air conditioning (HVAC) system delivers air that has been heated or cooled and dehumidified for occupant comfort. The HVAC system also provides the following features:

• | Power ventilation

• | Windshield defrosting

• | Side window defogging

During most operating conditions, outside air is drawn through the HVAC module by the blower motor. Additional outside air is also forced into the vehicle by the forward movement of the vehicle.

Within the HVAC module, air is pushed by the blower motor through the evaporator core, then through the heater core depending on the position of the temperature valve, then into the passenger compartment. For air conditioning or defroster operation at ambient temperatures above 7°C (45°F), the refrigeration system will chill the evaporator to almost freezing. As the air passes through the evaporator, the air temperature drops which causes the moisture in the air to condense on the evaporator core fins. This moisture leaves the vehicle by gravity feed through a drain hole, dehumidifying the vehicle.

From the evaporator core, some or all of the air may pass through the heater core, which is warmed by engine coolant. Any of the air which is not to be heated will mix with the heated air before entering the passenger compartment.

When the RECIRC mode is selected, most of the air entering the HVAC module is taken from the passenger compartment (recirculated). Recirculated air is most likely cooler than the outside air.