The Weathermaker is used for gas heating (last heating about 3 months ago) and for AC. Yesterday, when the thermostat was off, I heard a noise and noticed that the inducer motor (the round, black motor near the top) was sometimes running. It would run for a short time, turn off for a while, then run again. At that time, the red LED was flashing (23, I think, for pressure switch failure). I shut off the furnace at the emergency switch. Later on, I turned it on again with the same result. I turned it off again and much later, turned it on and turned on the AC at the thermostat. After an hour of AC, the LED was constant and it still is. However, the inducer motor still comes on for a few seconds then is off for at least a few minutes (the off time seems to vary).

What does the inducer motor do, and is it normal for it to run like that when the thermostat is off? I don’t think I noticed that before. The only repair done on it was in January 2007 when it wasn’t working at all and the circuit board was replaced.

Thanks for any help.

Sounds like the control board is acting up again