I recently had a GMH8 goodman furnace installed in the summer and after it was installed it fired right up, but now that I don't need the air and its time to use the furnace it won't ignite. It starts to cycle but when its time to ignite the burners it shuts back off and tries to ignite again. When I checked the light on the circuit board it has a continuous flash. Could this be a bad connection somewhere? If so where should I check?

Does the flame ever actually come on?

I work almost exclusively on goodmans, I will try to help you out if I can, I will be asking a lot of questions and hope you can answer them.

No there is no flame at all

Do you have one or two pressure switches? Does the glow plug actually glow red?

Most likely not a bad connection. Probably something much more simple. Does your furnace have a metal vent or plastic vent? I will stay here for a few minutes and try to help you out one on one. Please try to replay as quickly as possible. I have some ideas as to what the problem my be, but I will need to ask questions to determine your problem.

I'm not exactly sure what your calling a pressure switch. Are you referring to the switch behind the cover that is pressed in when the door is on?

It has a metal vent

There is a motor that has a orange tube coming off it. The orange rubber tube leads to the pressure switch. Are there two of these . Or just one?

The tube tees off and goes to 2 switches side by side

Try this. Turn power off to furnace.. wait five seconds, turn power back on to furnace.( make sure thermostat is turned way up) Your combustion blower(draft inducer) will start to run, stick the tubes going to each pressure in your mouth and suck on them, Keep sucking on them( this will suck the pressure switches closed), suck on them long enough to see if you get flame.If you do get flame let me know.

I tried it twice and no flame, I could smell the gas as it tried to cycle, then after awhile it just shut back down

Just keep in mind, its under warranty,, call the installer

Are you seeing any orange glow of the glow plug. wmproop is correct. If the furnace is less than one year old, the original installer is responsible for proper operation of the unit. I realize that you are probably trying to fix it yourselft because you can't contact ythe installer on the weekend. I would really like to help you, but it is hard for me to help when you don't have full understanding the furnace. Im betting that it will be an easy fix for a trained furnace tech. I really do wish you good luck(sorry I can't help) and please let me know how it turns out. You should not be charged for repairs from original installer( if furnace is indeed new)

I couldn't see the glow plug glowing. Yea the furnace was installed in July 08 but I'm not really thrilled with the installer because after he was finished he charged twice the quoted price and kind of did a sloppy job, I was just trying to not have any more dealing with him if I don't have too.

I really feel for you. But you have to get in the right mindset. You paid (more than you wanted to) for a professional install. You are entitled to complete warranty and service work on this unit. Call the installer and let them know what is going on. They need to fix this( you paid for it). If you don't get along with the installer, just try not to be there when they come to fix it. But it is definaltly their responsibility to fix your problem. You should not have to stress about a new furnace that doesn't work, you should be able to feel good that you have a warranty that will cover this.

Hope that this all works out well for you. Please keep me posted.

I have determined that the problem lies with the glow plug ignitor. I did see it glow once when it was trying to cycle but as quick as it came on it went out and it seemed like it came on too early. If you manually light it it will cycle just fine, runs till the desired temp and shuts off normally.