Author Topic: Bright Orange Flames  (Read 1538 times)

Offline jamie

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Bright Orange Flames
« on: February 13, 2019, 12:46:11 PM »
Good day all!

I have a goodman furnace that went off on high limit. It was installed in May. Customer said he changed the filter but did not reset. I went to look. Reset the high limit and furnace fired up no issue. The Flames are bright orange. No blue really at all. I think the furnace may be oversized, about 1100 sq ft, it is a 60K 2 stage furnace but not sure that would cause the bright orange flames, furnace is not dirty, the intake does not seem to be blocked. Gas pressures all good. CO at the vent was 11PPM, 0PPM in the plenum. The temp in plenum on low fire was about 118, high fire about 130. He only has 2 return airs upstairs hallway. He also had some heat registers closed that I told him to open.
Anyone have this issue before or can  guide me to see if there is anything else I should look for?

Thanks!!

Offline Admin

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Re: Bright Orange Flames
« Reply #1 on: February 13, 2019, 06:57:41 PM »
You could just lock in into low fire if you think it's oversized, but I don't think this would cause orange flames.

Usually lack of air or dust will cause the flame to burn orange.  Does it have a sealed burner box, or does the furnace door seal everything?  Do the flames change color when you remove the door?  Remove the burners and give them a good cleaning.  I would also check to see what size orifices are installed.

Doesn't the limit reset automatically?  Was it stuck open?

Offline jamie

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Re: Bright Orange Flames
« Reply #2 on: February 18, 2019, 06:58:28 AM »
I locked it into low fire. Flames don't change with door off. Its unsealed combustion box. The high limit was stuck open. Did not reset itself.
Do you think the orifices would be the wrong size from factory?

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Re: Bright Orange Flames
« Reply #3 on: February 18, 2019, 10:19:56 AM »
It’s very unlikely but I would clock the gas meter just to make sure it’s firing at the right input.