Ambient Temperature Sensor / Switch HVAC: Description and Operation

The ambient air temperature sensor is a temperature-sensitive resistor whose resistance varies inversely with temperature. As outside air temperature increases, resistance decreases. As outside air temperature decreases, resistance increases.

The heater and A/C programmer monitors the outside temperature signal and uses this information to display outside temperature on the heater and A/C control VF display and helps determine command signals.

The ambient air temperature sensor value can be updated by pressing the OFF, AUTO and VENT buttons on the heater and A/C control assembly at the same time. This function will update ambient temperature sensor to the current temperature reading.