Dakota 2WD V8-4.7L VIN J (2005)
Housing Assembly HVAC: Description and Operation
All models are equipped with a common HVAC housing assembly (1) that combines A/C and heating capabilities into a single unit mounted within the
passenger compartment. The HVAC housing consists of the following:
-
HVAC housing - The HVAC housing consists of an upper housing and a lower housing that are attached together by screws and metal retaining
clips and is mounted to the dash panel behind the instrument panel. The HVAC housing contains the heater core (2), blend-air doors and actuator
(3), A/C evaporator (4), blower motor (7), evaporator temperature sensor (8), mode-air doors and actuators (9), floor distribution duct, foam seals
and the HVAC wire harness.
-
Air inlet housing - The air inlet housing is mounted to the right end of the HVAC housing and contains the blower motor resistor (5) and the
recirculation-air door and actuator (6).
The heating-A/C system is a blend-air type system. The two blend-air doors control the amount of conditioned air that is allowed to flow through, or
around, the heater core. This single zone heating-A/C system uses only one blend door actuator.
The A/C system is designed for the use of a non-CFC, R-134a refrigerant and uses an A/C evaporator to cool and dehumidify the incoming air prior to
blending it with the heated air. A temperature control determines the discharge air temperature by operating the blend door actuator, which moves the
blend-air doors. This allows an almost immediate control of the output air temperature of the system. The two mode door actuators operate the mode-air
doors which direct the flow of the conditioned air out the various air outlets, depending on the mode selected. The recirculation door actuator operates
the recirculation-air door which closes off the fresh air intake and recirculates the air already inside the vehicle. The electric door actuators are connected
to the vehicle electrical system by the HVAC wire harness. The blower motor controls the velocity of air flowing through the HVAC housing assembly
by spinning the blower wheel within the HVAC housings at the selected speed by use of the blower motor resistor.
The HVAC housing must be removed from the vehicle and disassembled for service of the heater core, A/C evaporator, blend-air and mode-air doors.
The air inlet housing must be removed from HVAC housing for service of the recirculation door actuator and the recirculation-air door.
