Outside Air Valve

The Outside Air Valve Vacuum Actuator has no vacuum applied for every Mode Selector position except MAX (position 2). The actuator bellows are expanded. The Outside Air Valve is in position A. This opens the Outside Air Inlet and lets outside air into the plenum.

When the Mode Selector is moved to MAX, vacuum is applied to the Outside Air Valve Vacuum Actuator. The bellows are drawn in and the valve is moved to position B. Air from inside the car is pulled into the plenum.