Thermal regulator or internal bypass needs to be replaced
There are very few moving parts in your furnace. The only component that would normally do this is the fan. You can turn on the fan only at the thermostat. Try turning on the "fan only" and listen to the furnace. The belt may need replaced, or the fan motor. You can repair yourself if it is the fan motor or belt. The belt is the same as a fan belt on your car, and it replaces the same.
166 views
Usually answered in minutes!
×