I have a Keeprite N9MP1075B furnace with a fan that won't shut off. The AC starts and stops as required, I tried the heat as well and it comes on and off no problem, but the fan will run 24/7. The fan switch is on auto, not on, and even tried a different thermostat and had the same results. I have read that I may have a stuck fan relay and try giving it a tap to loosen it up but I can't seem to locate it on my system. I have been told I might have to replace the board as the fan relay may be located there, the circuit board is ST9160B 1084.
Any help would be appreciated.