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flame color?

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When I began in this industry I was taught that a gas flame should be "blue with yellowish tips". I believed that then but I found out that this was not true.

I have NO IDEA what a "strong yellow flame" really means. I will say this. Dial a gas burner in and then point a fan at it. You will see a heck of a light show!

No, color is not the end all, but sometimes it can tell you that there is an issue that NEEDS TO BE TESTED. Under gassed maybe?? Over gassed?? Flue spillage??? Curtain or eddy effect?? Cracked HX?? Leaking supply plenum??

I could list quite a few reasons for funky colors in a burn.

IMHO, just be glad someone at least noticed something, (although he/she may have seen a "nice blue flame with yellowish tips" that was making MEGA CO and said nothing)

I would also suggest that you contact the inspector and dig for details so that you can try to re-create the same conditions that existed when the inspector saw the "strong yellow flame".

Let us know what you find.

Mark H

Comments

  • Timco
    Timco Member Posts: 3,040
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    My fyrite is on a job and I will test of course, but I got a call today about a furnace that a housing inspector says has a "strong yellow flame". Has anyone had this called out? He had no opinion about CO level or gas pressure...just flame color. I was under the impression that flame color had nothing to do with it...

    Thanks, Tim
    Just a guy running some pipes.
  • Alan R. Mercurio_3
    Alan R. Mercurio_3 Member Posts: 1,620
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    I know guessing is not what we should be doing…….. However I would guess being Gas the inspector was expecting to see mostly blue for a flame color. Just 2 cents from an oil geek ;-)

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  • Fern
    Fern Member Posts: 11
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    Have to do the tests to tell

    > My fyrite is on a job and I will test of course,

    > but I got a call today about a furnace that a

    > housing inspector says has a "strong yellow

    > flame". Has anyone had this called out? He had no

    > opinion about CO level or gas pressure...just

    > flame color. I was under the impression that

    > flame color had nothing to do with

    > it...

    >

    > Thanks, Tim



    What if it is a modulating burner and in mild weather it could be modulating down and appearing more yello than normal, BUT COULD BE A LOT OF THINGS!
    thanks,
    Fern
  • Fern
    Fern Member Posts: 11
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    Have to do the tests to tell

    What if it is a modulating burner and in mild weather it could be modulating down and appearing more yello than normal, BUT COULD BE A LOT OF THINGS!
    thanks,
    Fern
  • Timco
    Timco Member Posts: 3,040
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    I'm sure your right on with that, but it seems strange that he would call out the furnace for flame color alone...as if blue flame = less than 100 ppm CO or something. What color are your flames?

    Tim
    Just a guy running some pipes.
  • Timco
    Timco Member Posts: 3,040
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    All I was told is Carrier, induced draft, non sealed combustion in a small crawlspace with pleanty of air. I was able to get this info from the HO on the phone.

    Tim
    Just a guy running some pipes.
  • [Deleted User]
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    And...

    Tell the inspector to go to Jim Davis' class to learn how to REALLY perform a CO inspection...

    ME
  • Empire_2
    Empire_2 Member Posts: 2,343
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    My Observation:

    Ever tap on the manifold gently, or dust around the furnace? You will see the result of dust being drawn in through the primary aire on the burners. Now,...Stay with me on this,. As you crawl to the unit, What is happening? I'll bet there is dust being disturbed and there is your yellow tips on the flame.

    Just thought it might explain this problem....

    Peace

    Mike T.
  • Ron Schroeder
    Ron Schroeder Member Posts: 998
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    If it's a gas flame that would be something wrong with no further testing needed to know it was wrong. Still needs to be tested to get it right.

    If it's oil, proper flame color changes so much from installation to installation that the eye is nowhere near "calibrated" to judge.

    I have seen experienced burner techs adjust a burner several times to what they thought was the same flame and actually be 5% or more different in CO2.

    Ron
This discussion has been closed.