Unused flue downdraft

WNelsonIII Posted By WNelsonIII, Nov 13, 2012 at 8:22 PM

  1. WNelsonIII

    WNelsonIII
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    Nov 13, 2012
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    Just trying to see if anyone else has had the same problem. I just purchased a Harman Oakwood for this winter. The stove is installed in the basement and there is a fireplace on the first floor above the stove. I never intend to use the fireplace with the Oakwood in the basement. Both these flues are in the same chimney with one chimney cap. Occasionally there is some smoke that downdrafts through the fireplace flue and out of the fireplace. I was wondering if anyone knows of a way to prevent this without completely closing off the fireplace.
     
  2. begreen

    begreen
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    Nov 18, 2005
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    Welcome to the forums. Was this install inspected? It's against code to have this on a common flue with the fireplace. The air from the fireplace is most likely diluting draft and cooling down the chimney. That's a recipe for creosote buildup. I would drop a liner all the way down to the stove. With a proper top cap that will stop the downdraft. The fireplace damper should be screwed shut with a sign in it saying that it can not be used as a fireplace.
     
  3. corey21

    corey21
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    Sounds like the fireplace is being a draft hog.

    Welcome.
     
  4. WNelsonIII

    WNelsonIII
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    Nov 13, 2012
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    It is a single chimney with two flues with a single chimney cap covering both flues. One flue for the fireplace and a separate flue for the wood stove. It seems as though the fireplace damper is not closing tightly allowing smoke to come in from the fireplace flue. Is there a way to seal off the fireplace flue that I am not using without completely closing off the fireplace?
     
  5. begreen

    begreen
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    Nov 18, 2005
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    Ah, ok, that is a different animal. This is a common issue. There needs to be a height separation between the two flues. Otherwise the idle flue can siphon the smoke from the adjacent flue. Here is a product to solve the issue.

    http://www.extendacap.com/
     
  6. Beer Belly

    Beer Belly
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    Oct 26, 2011
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    Maybe two Chimney caps, with the unused one installed lower ?
     
  7. EatenByLimestone

    EatenByLimestone
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  8. branchburner

    branchburner
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