I can't get my furnace to turn on. If I have the selector set on heat and the fan on the on position I can hear the relay click when I move the temperature up and down, if the fan is set on auto I h...
Check carefully for a "mechanics switch" inside the unit it could have been accidentally bumped off while cleaning or trouble shooting. Happened to a unit we were working on last Sunday. Follow the 12v leads going into the furnace, it should be before the circuit board.