Temperature Control

The operator controls air outlet temperature by positioning the temperature knob. The knob controls the cable to the blend flap. The flap is linked internally to a secondary air-direction flap that optimizes airflow through the unit by ensuring the airflow does not enter the heater core area thereby preventing any unwanted hot/cold air bleed.

Engine coolant is flowing constantly through the heater core. There is no water valve. Failure of the flap to block off air flow through the heater core would provide constant heated air in the vehicle.