Does this sound like a faulty flame sensor?

[Grif]

Howdy folks,

I have a three year old Goodman two-stage LP furnace (GMH95) that's giving me a problem. When I call my heating and cooling guy I want to sound like I know what I'm talking about.

Here's the problem:
About 70% of the time when the furnace tries to ignite, the electronic igniter glows red for about 7 seconds but the burners don't ignite so the igniter turns off. It tries again after a few seconds and if there is no ignition, it gives up. If I turn the thermostat off and back on, it will go through the process again and will eventually ignite, sometimes after one or two more resets.

As a result, I wake up to and come home to a cold house but can get the furnace to kick on after a few tries.

This sounds like a likely bad flame sensor, right? This is all under warranty but I'd like to hear your thoughts before I talk to my heating and cooling guy so I don't sound clueless.

Thanks,
Grif

[phbsales]

Maybe.......

Do the burners actually ignite and go off after a few seconds, or do they never ignite?

[chillitech71]

If the burners do not ignite, then it is NOT a flame sense issue.

[Grif]

Maybe.......

Do the burners actually ignite and go off after a few seconds, or do they never ignite?

Thanks for the quick reply, phbsales. When the burners light, they stay on. The problem is getting them lit. I can look through the peep hole in the cover and I know when I see red, it's the electronic igniter glowing. When I see blue, the burners have ignited. I never see blue for just a couple seconds; when it ignites, it stays on.

[beshvac]

Maintenance should be done on that furnace every year, when was the last time?

[big sky hvac]

Like what was stated earlier, if the burners do not light, it's not a bad flame sensor. If the ignitor is now glowing through it's entire warm-up period, there may be a pressure switch opening or the circuit board is faulty. It could also be several other things, but it's hard to say without seeing it. I wouldn't be concerned about what to tell the tech, it's his job to diagnos it. Just call and tell him that the furnace is intermittently working. When he arrives to look at it, describe to him what you've observed and let him fix it.

[firecontrol]

Howdy folks,

I have a three year old Goodman two-stage LP furnace (GMH95) that's giving me a problem. When I call my heating and cooling guy I want to sound like I know what I'm talking about.

Here's the problem:
About 70% of the time when the furnace tries to ignite, the electronic igniter glows red for about 7 seconds but the burners don't ignite so the igniter turns off. It tries again after a few seconds and if there is no ignition, it gives up. If I turn the thermostat off and back on, it will go through the process again and will eventually ignite, sometimes after one or two more resets.

As a result, I wake up to and come home to a cold house but can get the furnace to kick on after a few tries.

Thanks,
Grif

By calling and telling the service company exactly what you wrote above....... you're already sounding more informed than possibly 90% of the customers that call more than likely.

Tell them just what you wrote and allow their technician to diagnose what is going on. Sometimes giving too much information, especially to the technician, can in some cases sway them to jump on what you think it is.

They're there for two things, fix the problem and leave with you being a happy customer. Sometimes making the customer happy gets in the way of digging deep enough to find the real problem.

Trust them to know what they're doing and to take the information you've supplied here and make things work perfectly again.

[HVAC dawg]

:payattention: I would just say everything that you all just said. Have a tech out , shouldn't be too bad to troubleshoot.

[Grif]

Good advice, everybody. I think I know enough to sound knowledgeable when I talk to the tech.

Regarding the Goodman warranty, do you folks have positive experiences with the company? I ask because I see this on the website:

"To receive warranty online registration must be completed within 60 days of installation."

When it was installed three years ago, I never received any registration information from my tech and did not know I had to register. On the Warranty and Registration Lookup section of the Goodman site, my name is not found in their database. I can look up by serial number but am not sure where this is located on my furnace. I'm worried the warranty will not be honored because I did not complete any registration when the furnace was installed.

[slowguy]

I am a Goodman dealer. I sell many of them. They have, until recently, not had a very good name because of the failure rates of the furnaces even though they outsell every other manufacturer in the country. THis was mainly because anyone could buy and install Goodman, you wouldn't believe some of the installs I've seen on service calls - I'm surprised they stayed running for a week after the install.

If your furnace is still under its warranty period, and you call someone who is a goodman dealer/ installer, than it won't matter if you sent in the paperwork. That can all be looked up by the model and more importantly the serial. Your parts will be covered, but probably not the labor.

It's not the flame sensor if it will only ignite intermittently.

[Grif]

If your furnace is still under its warranty period, and you call someone who is a goodman dealer/ installer, than it won't matter if you sent in the paperwork.

Thanks for this information, slowguy. My heating contractor is a Goodman dealer so it sounds like there won't be any issues with getting the parts covered.

[beenthere]

If you want to sound intelligent when talking to your tech. just tell him you saw the HSI glow, but the burner never ignited.

If you try telling him more then that. You won't sound intelligent.

[btuhack]

If you try telling him more then that. You won't sound intelligent.

You have me giggling and shaking my head

[jmyahtzee]

I cant remember what goodman furnace it was or who made the gas valve for them but i remember a problem goodman had with the hsi being energized for about 9 seconds and then right when it would shut off the gas valve would come on. As it worked out on some furnaces the gas valve had a 1 second delay on it. I think it was white rogers but i cant remember.

[Serviceyourac]

Why would someone care to sound knowlegeable to a service tech. When people explain things to me on a service call it helps but I will still check everything anyway

[Grif]

I thought I'd post an update:

The problem was a bad gas valve. Parts were covered under warranty. Labor was $$$$ out of my pocket. The contractor said the gas valve went bad probably because the gas pressure was turned down too low. He adjusted this and installed a new gas valve and all is well.

Thanks everybody.

[Texas-Tech]

I thought I'd post an update:

The problem was a bad gas valve. Parts were covered under warranty. Labor was $100 out of my pocket. The contractor said the gas valve went bad probably because the gas pressure was turned down too low. He adjusted this and installed a new gas valve and all is well.

Thanks everybody.

Sounds fishy to me, since when did low gas pressure ruin a valve?

[misternash]

i really wouldn't worry so much about "sounding knowledgeable". let the folks you pay do their job. i'm honestly not trying to be rude here. if you trust someone enough to bet your comfort on their abilities, chances are they're gonna know a whole lot more than you. if they don't, i'd be exploring other avenues...

and i was wondering the same thing as texas-tech.

[SuperPro]

Did he check the gas pressure first before replacing the gas valve? More then likley it was low gas pressure causing the furnace not to light.

[Methanemann]

I cant remember what goodman furnace it was or who made the gas valve for them but i remember a problem goodman had with the hsi being energized for about 9 seconds and then right when it would shut off the gas valve would come on. As it worked out on some furnaces the gas valve had a 1 second delay on it. I think it was white rogers but i cant remember.

I have seen that over and over, it seems like if the GV opens just a hair later, it wont ignite. Always on a goodman. If there is any air in the line at all, it wont ignite. I always thought it was some type of safety. Should have known better. Seems like if the HSI gets a little weak, there won't be enough left over heat in the HSI to get the job done. There will probably be a lot of these in the near future.

[DeerHunter75]

I thought I'd post an update:

The problem was a bad gas valve. Parts were covered under warranty. Labor was $$$$ out of my pocket. The contractor said the gas valve went bad probably because the gas pressure was turned down too low. He adjusted this and installed a new gas valve and all is well.

Thanks everybody.



Did he run a few cycles AFTER adjusting GP to see IF that corrected it ?

Is he the one who installed it 3 years ago ?


Just doesn't sound right to me.

[carls]

typical goodman control board problem