Hey guys, I've been looking through these forums but haven't found an exact answer to my question, so figured I'd start my own thread. I have an American Standard gas furnace that uses a glow plug-style ignition system to light the gas, but the furnace only blows cold air. Let's see if I can get all the details here... The problem started a couple days ago with the furnace blowing cold air after being turned on after turning off the thermostat for the night. I went down to the basement and read the panel, turning the gas switch off, then the power, then back on. Once back on the glow plug lit up, a few seconds later I heard the click of the gas turn on, then the burners lit up and everything worked fine. The same problem happened 2 nights ago and was resolved in the same way. This morning, same thing, only now the furnace won't light up. I watched a cycle - hopefully this helps in diagnosing what's going on... after shutting everything down, and turning the gas and power back on the glow plug lights up. The gas clicks on and a few seconds later the gas tries to light (I see a flame start in 2-3 out of the 6 burners) but then everything quickly goes out, including the glow plug. There seems to maybe be a timing issue where the glow plug lights up brightly, then almost turns off? A split second before the gas comes through the burners. It doesn't go out entirely when the gas kicks on, but its dimming at the exact time the gas flow starts. I don't remember if this happened before when I got the furnace to work, but I seem to recall the glow plug glowing brightly throughout the ignition process. As background, I've lived in this house 4 years and have never changed the igniter (glow plug thing) and I read in a different thread the life span of these is usually 2-4 years. I wasn't thinking this was the problem since it does light up and glow brightly, but I'm no expert :)
Thanks for any help you guys can give!
Andrew
