Heater Control Valve Vacuum Switch
WARNING: This page is about a different car, the 2009 Mercury Mountaineer, 2009 Ford Explorer Sport Trac, and 2009 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
The heater control valve vacuum switch applies vacuum to the heater control valve when the temperature blend door is in the full COOL position. The temperature blend door actuates the heater control valve vacuum switch with an arm attached to the RH side of the temperature blend door pivot shaft.
The heater control valve vacuum switch is mounted on the RH side of the heater core and evaporator core housing just below the defrost door vacuum control motor.