F 350 2WD Pickup V8-460 7.5L VIN G EFI (1997)
Heater Air Plenum Chamber: Description and Operation
The heater air plenum chamber is mounted to the dash panel in the passenger compartment. It contains the heater core, temperature blend door,
floor/panel door, and the floor/defrost door. The temperature blend door is controlled through a cable actuated cam located on top of the heater air
plenum chamber. The floor/panel and floor/defrost doors are both controlled by vacuum control motors located on the bottom of the heater air plenum
chamber.
The heater core is located in the heater air plenum chamber behind the heater core cover. The heater core cover allows the heater core to be removed
without removing the heater air plenum chamber.