I see no answer was put here, but I am having same problem, Goodman furnace. LED flashed 3 times. No heat. Please let me know what you think.

Manual says possible causes are

1. pressure switch hose blocked, pinched or connected impropertly
2. blocked flue and or inlet air pipe blocked drain system or weak induced raft blower.
3. incorrect pressure switch setpoint or malfunctioning switch contacts
4. loose or impropertly connected wiring

This is just a 2 year old unit, and was working fine last winter.

Let me know

burlington1

If the inducer motor is running but the furnace is not lighting. You can remove the pressure switch hose from the furnace, blow and suck lightly on the hose(other end on the pressure switch) you should hear it click. Put back together and give it a try. If its not working you may have a restriction in the vent pipe.