Grand Caravan V6-3.8L VIN L (2007)
Housing Assembly HVAC: Description and Operation
Front
DESCRIPTION
NOTE: LHD model shown in illustration. RHD model similar.
All models are equipped with a common HVAC housing assembly that combines A/C and heating capabilities into a single unit mounted within the
passenger compartment (Figure 1). The HVAC housing assembly consists of three separate housings:
-
HVAC housing - The HVAC housing is mounted to the dash panel behind the instrument panel and contains the A/C evaporator and the blower
motor resistor or power model (depending on application) and the particulate air filter (if equipped). The HVAC housing consists of a upper and a
lower housing that are attached together and has mounting provisions for the air inlet housing, blower motor, air distribution housing 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 recirculation-air door and actuator.
-
Air distribution housing - The air distribution housing is mounted to the rear of the HVAC housing and contains the heater core, blend-air doors
and actuators, mode-air doors and actuator and door linkage.
Figure 1 HVAC Housing Assembly
The heating-A/C system is a blend-air type system. The blend-air doors control the amount of conditioned air that is allowed to flow through, or around,
the heater core. The dual zone heating A/C system uses two blend door actuators.
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 actuators, which moves the
blend-air doors. This allows an almost immediate control of the output air temperature of the system. The mode door actuator operates 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 housing at the selected speed by use of the blower motor resistor or power model, depending on
application.
The air distribution housing must be removed from the HVAC housing and disassembled for service of the mode-air and blend-air doors. The air inlet
housing must be removed from HVAC housing and disassembled for service of the recirculation-air door. The HVAC housing must be removed from the
vehicle and disassembled for service of the A/C evaporator.
