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Something oozing out if thimble

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by sowers25, Nov 9, 2012.

  1. sowers25

    sowers25 New Member

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    I got home from work and found a blackish wet lookin stain coming down my brick profile from the bottom I my thimble. Anyone have any idea what it is and what's causing it?

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  2. Jags

    Jags Moderate Moderator Staff Member

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    Have you recently had wind and rain? If so it appears that you have had water intrusion. Only other culprit is creosote. Slow dirty burns.
  3. corey21

    corey21 Minister of Fire

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    Looks like glazed creosote that has turned to liquid creosote.

    If i saw that my stove would get shut down and the pipe would come off to be checked.
  4. clemsonfor

    clemsonfor Minister of Fire

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    I second the water in the chimney and washing creosote down into the house.
  5. Sprinter

    Sprinter Minister of Fire

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    Is that horizontal pipe section level, or at least sloped in the right direction? It's hard to tell from the pic, but it looks like it might be just slightly sloped. Sure looks like rain washed creosote or just soot to me. Even a relatively clean chimney might easily have just enough black stuff to get washed down and leak out the stovepipe, but as I understand, the pipe connections should be such that any water should not be able to leak out the connections unless there is a place for water to accumulate
  6. Oldhippie

    Oldhippie Minister of Fire

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    What do you have for a stove and how new are you to burning? Is this your first season? Do you have a temp guage on it anyplace? Any idea how clean you are burning?

    I think it's creasote from a not hot enough burn and/or with less than fully seasoned wood.
  7. sowers25

    sowers25 New Member

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    I have a 30 nc just got it up and running a few weeks ago. Yes it's my first year burning, my wood is mostly oak dead standing but will admit its probably got a little too much moisture in it. Just measured a fresh split with a mm and its reading around 26-28. The stove temp has been at least 350, having a hard time getting it to the higher ranges, probably on account of my wood.
  8. clemsonfor

    clemsonfor Minister of Fire

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    26% is pretty good! I think you may not have enough draft?

    As far as the slopped chimney that makes sense that it should slope out so water dont run in, but can we confirm that his is that way??
  9. Jags

    Jags Moderate Moderator Staff Member

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    RED FLAG. That stove should hit 600 without even trying. If you cannot get above 350F - you have a problem. First glance says wood!
  10. Sprinter

    Sprinter Minister of Fire

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    NC 30's are usually referred to as "heat dragons" around here. Do have a smoke problem? Dirty glass? Sounds like wood, or draft, or air supply problem? Does the fire flare up when you open the door (suggesting an air supply issue maybe)? Could there be a flue draft control that's closed?
  11. ozzy73

    ozzy73 Member

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    Make sure you take a pic of the inside of the stove pipe before you clean it.

    Lets hope its just a little water/creo mix.
  12. sowers25

    sowers25 New Member

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    No smoke problem as far as smoke bellowing out when I open the door. The glass does get dirty at the end o a burn, like when I get up in the morning after a all night burn, but clears up once I get it up and going again good. The fire does flare up when I first open the door to reload, but isn't that normal? All the drafts controls are open and working in proper order. I believe it's the wood because I have gotten it up to 500-600 on a few occasions with really good looking wood. All the wood I have is pretty fresh splits so it hasn't had a lot of time to air out
  13. Prof

    Prof Burning Hunk

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    What type of temps do you get on the pipe? If stack temps don't get past 320F you have a creosote factory. Oak takes a long time to get it below 20% moisture content.
  14. Sprinter

    Sprinter Minister of Fire

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    Unless somebody else has some other ideas, it sounds like the wood, and it probably is causing a lot of creosote. But you also have the problem of water leaking it sounds like. You have to track that down, maybe by taking some sections out of the stovepipe. Did you determine yet if there is a place in there where water could be accumulating? It really shouldn't be leaking. There are some people here very knowledgeable about pipes and chimneys.
  15. oldspark

    oldspark Guest

    Thats too wet.
  16. laynes69

    laynes69 Minister of Fire

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    Your wood is higher for a EPA stove, but also what size is your flue? These stoves aren't like the old ones that put alot of heat up the chimney. If the flue is too large, the gasses can condense and what your seeing will occur. We had it happen to us, and drier wood and a chimney liner solved all our problems.
  17. sowers25

    sowers25 New Member

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    The flue is 6" inside going to a 8x8 masonary on outside of house with a cap on top it hasn't rained here lately though unless hurricane sandy left some water in there somehow but I don't see how that could be considering I've burnt it a lot since then and it surely would evaporate. So I can't see how it could be water. When we put the black stove pipe through the wall I never sealed it with anything, should have I?
  18. clemsonfor

    clemsonfor Minister of Fire

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    I know its not what you want to burn but it will burn and get Way hotter than that. I know!
  19. Jags

    Jags Moderate Moderator Staff Member

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    Well....maybe, BUT it might have been a good thing that you didn't. Something needs to change. Obviously the fuel supply is suspect, but dumping into an 8 x 8 outside flue is going to AMPLIFY this problem.
  20. oldspark

    oldspark Guest

    Yea if he knows what he is dealing with, now he doesn't want a hot fire due to the creosote, time to start over and clean the chimney and try some dryer wood and see what happens.
  21. oldspark

    oldspark Guest

    How tall is that 8x8 monster?
  22. Sprinter

    Sprinter Minister of Fire

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    Good point. If it's not water, then it's liquidy creosote. Here's a good article on that subject and how best to take care of it. http://www.chimneysweeponline.com/hoburnout.htm

    I believe that creosote starts out as a liquid condensate, then hardens over time. However, that still doesn't explain how it's getting out. The pipe sections should be nested so that liquid can't drip out.
  23. Jags

    Jags Moderate Moderator Staff Member

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    the pipe is stubbed into the 8 x 8. Stuff drips down the walls of the 8x8 hits the horizontal run and then drips in behind the thimble wall plate. Ooey gooey mess.
  24. Sprinter

    Sprinter Minister of Fire

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    There you go. Sounds right. It might also be some condensed water dripping down after the water vapor from the fire cools in the 8x8. Others here are much more expert on flues, but you might have to consider lining the masonry flue.

    As for the wood, if you can't get truly dry wood now, it might help to use some biobricks or similar pressed log product. Some people burn them along with less than desireable wood. The idea is to get the whole load closer to 20% or less. I've never tried it myself, but it has been suggested here.
  25. corey21

    corey21 Minister of Fire

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    Sounds i like your wood is to wet combined with your chimney.

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