I have a goodman furnace that won't stay on.. the glow plug comes on and ignites the heat box, it will run then shut off... after it gets to desried heat,, then when u try to get it to run again it's like it shuts down after igniter being lit for about 10 secs, I've replaced batteries in thermostat and had new filter installed as well... it seems every time I go to loook at it I can get it to run as normall then my tenent calls and tells me it won't start after coooling of the house