Hi - I have a Goodman GPM furnace. It works intermittently. I replaced breaker, thermostat, Control board and surface igniter. All appears well on start up sequence ; blower runs and igniter heats up and then turns off as no gas comes out. Control board codes says ok. Can anybody recommend what to do next. The house and unit is 6 years old and I have had no problems until now. Thanks

labman

After the igniter heats up, check to see if you get 24 volts to the gas valve itself. If it gets power and doesn't open, it is bad. If it isn't getting power, check the connections to the control board.

sizl37

Just fixed this problem on my goodman furnace. It was the heat sensor. My furnace kept cycling on and off but would not let the flame burn. The sensor was full of carbon or soot. My ignitor would also light and then shut down. I removed the sensor and lightly sanded it with a 150 grit sand paper till it was shiney again. Works great now and it only took about 15min to do. just one screw to hold it down and then just unplug it and take it out. Make sure you cut the power to the furnace first. good luck hope this helps