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What Causes White soot?

Jim Davis_7
Jim Davis_7 Member Posts: 67
White soot is normally caused by firing at low temperatures or some type of venting issue creating some condensation. If the soot was yellowish then it would be more of a sulfur by product and that would be normal.


  • Mike20
    Mike20 Member Posts: 37
    White Soot

    I work on #4 and #6 fuel burners and I notice that the burners are producing White Soot on the boiler tubes. The soot is actually an Off white color and has the consistancy of powder. The burners are running efficiently with 12 Co2 or better. Any Idea what is causing this? Thanks- Mike
  • Ken_40
    Ken_40 Member Posts: 1,320
    It is a

    byproduct of combustion. Proably a white "ash" from good combustion, with oil having relatively high sulphur content - which results in an off-white residual being left behind. As long as the boiler rarely gets low enough in temperature, the white powder is harmless. If it gets wet, it is rather corrosive - although no where near as bad as what would have happenned 20+ years ago, when oil had over 4% sulphur content!

    A little sulphur, a litle water, we got H2SO4, a/k/a sulphuric acid. Take away the H2O, ya get basically harmless white powder(;-o)

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