Hi, first time user here. The inducer motor on my old furnace cycles on and off both when there is no call for heat, and also when the furnace is providing heat to my house. An HVAC guy told me that my thermostat was faulty. I replaced it and it continues to have a problem. I have a basic understanding of the sequence of events that a furnace goes through and I can not understand what would be causing this problem. Especially because the furnace continues to provide heat when the inducer motor goes on and off repeatedly.
I have seen this problem a couple times with some Honeywell thermostats and control boards.
Installing a bleed down resistor between W and C at the furnace may solve the problem.
Disconnect the low voltage wire from the W terminal and observe the furnace. If the problem still continues, it's the control board.