I have a Goodman GMPN060-3. When I turn off the furnace and start it, everything works fine. But it won't come on from when the thermostat sends heat demand signal. The LED light flashes twice meaning "pressure switch stuck closed". I noticed the venter motor did not stop at all between cycles (after flames go out when desired temp reached).
1) How long after burner flames go out, should the venter/blower motor stop ?
2) Is the motor staying in running/on condition keeping the pressure switch closed ?
3) If so what could be the problem ?