The temperature blend door, located in the heater air plenum chamber directs outside air to flow through the heater core for heating,
or to bypass the heater core for ventilation with unheated air.
It is controlled by the temperature control **** of the heater control located in the instrument panel.
A heater temperature cable (18518) connects the temperature control **** to a cam which operates the temperature blend door. When the temperature control **** is at the COOL position, the temperature blend door directs outside air to bypass the heater core. When the temperature control **** is at WARM, the temperature blend door directs outside air through the heater core where the air is heated.
Positioning the temperature control **** in any position between COOL and WARM causes the temperature blend door to direct more or less outside air through or around the heater core for whatever proportion of heated or unheated outside air is desired.
The air blends together as it leaves the heater core in the heater plenum chamber case for distribution.
Tuesday, March 22nd, 2011 AT 7:13 PM