The air temperature valve electronic actuator positions the temperature door according to the temperature setting of the temperature control on the temperature control knob. For the full COLD temperature setting, the temperature control returns approximately 12 volts to the air temperature valve electric actuator. When the temperature setting is changed to full HOT, the temperature door is moved to the warm position and the output drops to about 0 volts. For a temperature setting in the mid range, the temperature door is positioned according to the voltage supplied through the temperature control switch.

If the motor stalls when changing the door location, voltage is removed by the HVAC controller after 45 seconds in order to protect the motor.