Air Distribution System

Air Flow Diagram:

Air Distribution System:

Air utilized by the HVAC system is drawn into the blower module through the air inlet assembly at the base of the windshield and routed through the blower. The blower forces the air through the evaporator core where it is dehumidified and cooled. The air is then heated as required by passing through or around the heater core. Now conditioned, the air is directed by air valves in the A/C module to the outlets in the instrument panel, to the heater outlets at the floor, front and rear, or to the defroster outlets, depending upon the mode selected by the driver.

Air Inlet Assembly

The air inlet assembly provides outside (fresh) or inside (recirculated) air to the blower depending on the mode selected by the driver. The inlet air is varied by an actuator that is controlled by the heater and A/C programmer.

Blower Motor

The blower consists of a permanent magnet type motor and squirrel cage type fan. The blower operates at various speeds determined by the heater and A/C programmer.

The blower motor is cooled by having a small portion of blower output air recirculated through the motor housing through a rubber tube.
The blower is located in the passenger compartment near the right side of the HVAC module.

Air Distribution Chamber

After passing through the evaporator core the now cooled and dehydrated air will pass, all or in part, through the heater core. This will establish the desired air temperature as requested by the driver.
Once conditioned to the correct temperature the air enters the air distribution chamber. Valves in the air distribution chamber are positioned by the heater and A/C programmer. By varying the position of the distribution doors, the air distribution chamber is able to direct air flow to the floor, windshield or the upper ducts. Air always passes through the rear floor duct.

Ducts and Outlets

The ducting is the network of tubing used to get conditioned air from the A/C module to the instrument panel and rear seat outlets. There are two major ducts that are attached to the air distribution chamber.

1. Cross Car Ducts.
2. Rear Seat Duct.

The cross car ducts are attached to the back of the instrument panel. It receives air from the distribution chamber and delivers it to the instrument panel outlets and pass through ducts to the side windows.
The rear seat duct receives air from the bottom of the distribution chamber and delivers it through two outlets at the rear of the front seat center arm rest or console.