Heating and Defrosting

Heating And Defrosting:

The heating and defrosting system operates as follows:
- Controls the temperature and during A/C operation, reduces the relative humidity of the air inside the vehicle.
- Delivers heated or cooled air to maintain the vehicle interior temperature and comfort level.
- Cooling or heating can be adjusted to maintain the desired temperature.
- System uses a reheat method to provide conditioned air to the passenger compartment.
- The blower motor draws outside air through the A/C recirculating air duct from just below the windshield during all system operations except for MAX A/C cooling (when recirculated air is used).
- All airflow from the blower motor passes through the A/C evaporator core.
- The temperature is then regulated by reheating a portion of the air and blending it with the remaining cool air to the desired temperature.
- The temperature blending is varied by the air temperature control door, which regulates the amount of air that flows through and around the heater core, where it is then mixed and distributed.

A/C Evaporator Housing
The A/C evaporator housing has the following features:
- split case design
- located behind the instrument panel between the A/C recirculating air duct and heater air plenum chamber

The A/C evaporator housing assembly contains the following major components:
- A/C evaporator core
- heater core
- air temperature control doors
- heater air damper door







Heater Core
The heater core consists of fins and tubes arranged to extract heat from the engine coolant and transfer it to air passing through the heater core.







Blower Motor
The blower motor pulls air from the A/C recirculating air duct and forces it into the A/C evaporator housing where it is mixed and distributed.