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White powder building up inside gas insert

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by remerling, Jul 27, 2007.

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  1. remerling

    remerling New Member

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    My gas insert is about 2 years old. There is an ashy white powder building up inside the unit on the walls (there are fake brick panels on the back and side walls) and also on the top (inside). Is this due to some contaminant in my gas supply, or perhaps a sign of air leaking into the unit around the seal on the front of the unit ?

    Thanks. I appreciate any input you have...

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  2. jtp10181

    jtp10181 Minister of Fire

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    You guessed at the two possible problems. LP gas is more often the culprit. It could also be that you have a stubby fresh air liner ran and its sucking in contaminants from the old chimney.
  3. elkimmeg

    elkimmeg Guest

    I'm with JTP gas comtaminents not all that uncommon but can be cleaned
  4. webbie

    webbie Seasoned Moderator Staff Member

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    My guess is that it is slight corrosion of certain metals and other materials inside the unit - maybe moisture baking out of the ceramics and some of the aluminized steel...and even some paint outgassing and then settling down.

    That's my take.......of course, it also can be stuff from the LP, but it may be reacting with these other materials.
  5. stoveguy2esw

    stoveguy2esw Minister of Fire

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    look on your burner tube itself , around the orifaces in the tube where the gas comes out , if there is a buildup of this stuff there then webby is right , clean with alcohol (non drinkable mind you :) ) should remove it. if not present in this area but is in the other regions you mentioned , check flue if applicable , or log position , flame should not directly contact logs , at least not heavily , this impingement causes a rich burn which can leave either a whitish or sooty residue , depending on amount of impingement or log material. hope this helps. by the way if this unit is vent free , i would avoid using it until the culprit is found and fixed (not due to danger as vent free's are extremely safe , but they can have a tendancy to cause yellowing in drapes, white paint etc, if they are burning rich)
  6. jtp10181

    jtp10181 Minister of Fire

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    I would recommend calling the dealer for an annual service cleanup and testing. Most MFG's recommend the gas fireplaces be serviced annually just like furnaces.
  7. remerling

    remerling New Member

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    Thanks to all for the inputs. I'm burning natural gas, not LP. The unit has separate intake and exhaust, both run up to the top of the chimney. There are signs that the seal around the glass front of the unit may be leaking in one small spot, and that's probably enough to make it burn rich and make soot inside the unit. Guess I should look into having the seal replaced...
  8. jtp10181

    jtp10181 Minister of Fire

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    Soot = Black

    White power would be from dust or other contaminants getting inside the unit and burning. I see it a lot on a B-Vent units which use room air for combustion (I know yours is not "supposed" to be using room air).

    It can also be from bad ember placement (the little green stuff that glows), or too much embers. We had one recently where the embers were in a big heap and the logs were all mis placed. There was also some other crud on the burner that did not belong. The whole unit was caked with white powder inside. Needed a new burner, grate, and logs.
  9. Shane

    Shane Minister of Fire

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    I would look at gas contaniments and/or air to fuel mixture. Usually flame impigmnet is indicated by actual black soot build up.
  10. Michael6268

    Michael6268 Feeling the Heat

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    No chemist here, but I always thought is was from the summer moisture/humidity reacting with the residue on the inside of the firebox. I covered my air intake/exhaust this spring and put some "moisture rid" inside the unit this year and noticed a big difference in the amount of "white stuff" on the interior.
  11. Shane

    Shane Minister of Fire

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    That's interesting Michael. Maybe some more exploration into the matter is necessary. I honestly always assumed/was taught it was impurities in the gas but if what your saying is the case or atleast a contributing factor then it's something that we need to keep in mind.
  12. BLAZE KING

    BLAZE KING New Member

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    One of the byproducts of the combustion process in a gas appliance, is a mineral which can show up as a white film on the ceramic glass of the viewing door. The composition of the deposit varies widely from various locations and also from time to time in the same location. You may have the problem for a time and then not see it for many months when it will reappear in your area. It seems this is associated with the varying sulfur content of the gas.
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