Goodman GMP075-3 ignition issue
I have a Goodman GMP075-3 furnace. The draft inducer comes on, the control board clicks, the ignitor bar glows, the control board clicks again and the glow bar stops glowing. It seems like the gas valve isn't opening to allow gas to ignite, at all. I've replaced a rollout switch, the flame sensor and the control board. What's next? The pressure switch seems to be fine as I can blow and suck in it to make it open and close. I can do the same with the inducer by blowing into the hose and air goes through it without a problem. Could the limit switch need replacing? How about the pressure switch? I haven't put a volt meter on the pressure switch to see if it's passing 24 volts yet. Is it possible that the gas valve itself has gone kaput? I know that Goodman furnaces aren't the best in the world, but I can't afford to replace it just yet. I'd like to be able to make it through this winter first, then I can purchase a new furnace in March.