Goodman GMH8 / AMH8 error codes

Every checked code for the Goodman GMH8 / AMH8 range, with what it means and whether you can fix it yourself.

Error codes

Code	Meaning	What you can do
light off	No power to the control board	Safe checks first, then a pro
1 red flash	Ignition failure or gas valve fault (depends on model)	Safe checks first, then a pro
2 red flashes	Pressure switch closed when it should be open	Call a pro
3 red flashes	Pressure switch not closing	Safe checks first, then a pro
4 red flashes	Overheat (depends on model)	Safe checks first, then a pro
5 red flashes	Sensor fault or overheat (depends on model)	Safe checks first, then a pro
6 red flashes	Overheat / flue or venting fault (depends on model)	Depends on your model
7 red flashes	Flame loss or ignition failure (depends on model)	Depends on your model
8 red flashes	Ignition failure or flame loss (depends on model)	Depends on your model
red light flashing rapidly	Electrical fault or configuration error (depends on model)	Call a pro
steady red light	Normal operation or control board internal fault (depends on model)	Depends on your model