gpmn100-4 firing problem - Contractor Talk - Professional Construction and Remodeling Forum

desperadol30 · 12-29-2005, 11:21 PM

I have a goodman 100-4 that has good gas pressure but will notstay lit at times. It has plugged up with black stuff in the past. Teh burners are not looking the same as it has in the past. Anyone know of any checks?

Bestheating · 12-30-2005, 11:44 AM

That furnace is quite straightforward to troubleshoot. I am concerned about your indication of the burners looking different. Is it on LP gas? Is it sooted up? You need to be sure on this...
As far as the burners going out, check and clean the flame sensor. Have you checked the gas pressure on BOTH sides of the valve? After that, post a note with a little more detail.

rabadger · 12-30-2005, 03:49 PM

Several years ago Goodman had a problem with burner assemblies sooting. I remember sending several back per month under warranty. I do not recall what years this took place.

desperadol30 · 01-01-2006, 01:16 PM

Quote:

Originally Posted by desperadol30

I have a goodman 100-4 that has good gas pressure but will notstay lit at times. It has plugged up with black stuff in the past. Teh burners are not looking the same as it has in the past. Anyone know of any checks?

everythigh checks out right code wise. The burners just don't seem to light up the same as before like they use too. It is like some of them will flame out of hte heater when the cover is off sometimes. I had to adjust the gas pressure and it seemed to help a little bit. It is on lp gas also. The flame sensor is ok. It plus up usually after a week when I first start it, but now plugged up shortley after I cleaned the condensate lines.

desperadol30 · 01-01-2006, 01:17 PM

Quote:

Originally Posted by rabadger

Several years ago Goodman had a problem with burner assemblies sooting. I remember sending several back per month under warranty. I do not recall what years this took place.

where can i get new burners cheap?

mdshunk · 01-01-2006, 01:23 PM

Quote:

Originally Posted by desperadol30

It is like some of them will flame out of hte heater when the cover is off sometimes.

That gets me looking at things like clogged flue or popped heat exchanger.

Quote:

Originally Posted by desperadol30

I had to adjust the gas pressure and it seemed to help a little bit. It is on lp gas also.

Ahhh! That statement gives me shivers. What caused you to think that you had to adjust the pressure? Do you own a manometer? Have you checked the gas pressure on both sides of the gas valve? Arbitrary gas presssure adjustments are a sure fire way to get yourself in big trouble.

Bestheating · 01-03-2006, 07:28 PM

Just checking back to see if you found a solution. I agree that you should not necessarily be making gas pressure changes...especially without a manometer. I highly suspect you are going to find a plugged heat exchanger. Here comes our friend CARBON MONOXIDE!!! He still makes house calls! This is a dangerous area to be playing if you do not have the equipment and expertese. Let us know what happens!

rabadger · 01-04-2006, 12:03 PM

check with the supply houses that sell Goodman. Have model number and serial number. You may have to have a HVAC service contractor change the burners.

If this thing worked for several years, what has taken place that caused the change? Are you sure it is the furnace? Are you sure you have a good sealed heat exchanger and not getting air turbulance during the burn?

Get a qualified tech with the right meters and tools.

zone2428 · 01-28-2006, 10:08 AM

sounds like you need a good cleanig in the furnace(burners heat exchangers) and make sure your gas press,is set exactley per name plate (10WC).