Control Assembly, HVAC

The climate control assembly has three system controls:
^ The A/C heater function selector switch combines a vacuum selector valve with two electrical switches to supply battery positive voltage (B+) to the A/C clutch circuit and the blower motor control circuit.
^ The temperature selection is accomplished with a potentiometer connected to the electric blend door actuator that controls positioning of the temperature blend door. Movement of the control knob from COOL (blue) to WARM (red) causes a corresponding movement on the air temperature control door and determines the temperature that the system will maintain.
^ The blower motor switch controls blower motor speed by adding or bypassing resistors in the heater blower motor switch resistor.