Temperature Control

TEMPERATURE CONTROL
Temperature control is accomplished moving the temperature valve inside the heater and A/C module assembly to direct air through or around the heater core. When all air is forced through the heater core, maximum heating is obtained. When all air is routed around the heater core, no heating is obtained.
The temperature valve is operated by the A/C temperature valve actuator, which mounts on the heater and A/C module assembly. The actuator contains a reversible DC motor, which responds to a voltage signal from the temperature knob in the heater and A/C control.
With the ignition switch in RUN, battery voltage is present at the heater and A/C control temperature knob.
When the temperature control knob is moved fully to the left (COOL), less than 1 volt is applied to the A/C temperature valve actuator, the actuator operates the temperature valve to completely block air flow through the heater core, and no heating is obtained.
When the knob is moved fully to the right (WARM), battery voltage is applied to the A/C temperature valve actuator, the actuator operates the temperature valve to direct all air through the heater core, and maximum heating is obtained.