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flue size on EKO 40?

Post in 'The Boiler Room - Wood Boilers and Furnaces' started by husker, Jan 14, 2009.

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  1. husker

    husker New Member

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    I know 8" chimney is supposed to fit these boilers, but my black double wall cleanout tie seems slightly to big to fit inside the flue pipe. Am I missing something here? Do I need a collar of some sort?

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  2. Dave T

    Dave T New Member

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    I've heard of this problem before you are right the pipe is slightly to big, a crimp tool like for house gutter downspouts can be bought anywhere and that can be used to crimp around the pipe to make it fit..REMEMBER fasten your pipe to the EKO to avoid future issues with the pipe backing out..Dave
  3. DMX_512

    DMX_512 Member

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    I thought the EKO 40 requires a 6 inch flue?
  4. husker

    husker New Member

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    The outer diameter of the stove flue is about 7 3/4". I can't believe I never seen this discussed here. I want to make sure the thing doesn't fall off while burning. The Supervent rep says to crimp the pipe to fit inside the flue but that doesn't seem like it will seal very well to me or be very stable. The rest of the chimney sections fit very well. I have also been told to "shim" up the flue with high temp caulk and tape so the pipe will fit snug over the outside. This should be a bolt up an go deal not something I have to gerry rig!!
  5. DMX_512

    DMX_512 Member

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    OK
    I was hoping that you were talking about the O.D. o the actual double wall flue pipe.
  6. Duetech

    Duetech Minister of Fire

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    According to the manual the EKO40 chimney flue is 7.8 inches (like we're gonna have one of those adapters in our local hardware?). When I bought my 40 though I was told 6 or 8 and since I already had the 6" left over from a wood furnace I was replacing I stuck with 6" and inadvertently overlooked the 7.8 part. But I found no one had a true 7.8" to 6" adapter so I had to build one of my own and since I had believed I could use 6" I did not include a new chimney as part of the purchase price for the system. If draft is the main concern here, the 40 has six 1 1/2" tubes where the 60 and 80 both supposedly have twelve tubes and they all three use an 8" chimney (!?!?). The 40 has one blower and the 60 and 80 have two but practically the identical chimney(!?!?). Warranty might come into question because of your selection here but obviously it's a manufacturing economics move where they buy basically one part that they can put on the most number of units and let the consumer do the adaptation. Adapters are probably readily available in Europe. The area of all six tubes in the 40 equals a little over 10.60 sq inches. The area of a six inch chimney is a little over 28.25 sq inches or 2.8 times the area of the heat tubes of the unit. In comparison the area of an eight inch chimney is a little over 50.25 sq inches or over five times the area of the tubes but only a little bit bigger than the natural draft of the boiler. The only real concern for the 6 inch chimney then is when the unit is in natural draft via bypass selection mode. By the mechanics of the boiler there are only a few ways where that much draft could be used and that would be by having one or both of the primary or secondary doors open during operation and since neither of those options are considered viable as modes of operation we are reduced to natural draft for start-up and the forced draft area of the heat tubes for normal operation which would seem to make 6" viable for the 40. It was suggested to me that I just buy a black 6" to 8" chimney pipe adapter for my set up which meant buying the crimping tool and adapter. I didn't like the fit so I built an adapter to hook right into a triple wall T right at the boiler flue outlet. That was a task but it's built heavier than the 4mm chimney flue that comes on the 40.
  7. DMX_512

    DMX_512 Member

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    Well this is interesting.
    Good thing I haven't cored my foundation yet.
    After looking back through spec sheets that i have down loaded i noticed that there are 2 different sizes quoted for the chimney flue diameter.

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  8. DMX_512

    DMX_512 Member

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    And here is the other Spec

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  9. husker

    husker New Member

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    Well the little ACE hardware store had a plain single wall 12" section with a bell end. The opposite smooth end fits like a glove over the stove flue (at least 4" deep) so I think I can just seal that with high temp silicone from the inside especially where seam on the single wall pipe is. The bell end goes into the double wall black tee pretty well although I had to press it back out some after trying to force it into the stove earlier. Nevertheless, this tee should fit pretty decent into the single wall section and I can finally get back to putting it all together. At least I know nothing is going to fall off.
  10. Duetech

    Duetech Minister of Fire

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    With that document there would be no problem with warranty. I have been using 6" since my installation in 06 and have not had a problem. I had been thinking I had seen it in print but I couldn't put my finger on it. Thanks! I used a piece of 6" id steel pipe I picked up at a salvage yard but it took a lot of tinkering to make everything work.
  11. Northwoodsman

    Northwoodsman New Member

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    I used an 8" tee type w/ cleanout, single wall flue pipe that fit over top of the EKO outlet. I secured it with 3 self tapping screws and sealed it with high temp sealer.

    There was a little gap between the flue piep and EKO outlet but with the screws and the sealer there are no leaks and all is working fine.

    BC
  12. husker

    husker New Member

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    That's basically what I ended up doing. An 8" x 12" single wall piece that fits tightly over the EKO and seal it up. With 3 self tapping screws it will be solid as a rock.
  13. stee6043

    stee6043 Minister of Fire

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    I too am running a 6" flue on my EKO 40. I ran an 8" T off the back of my EKO to an 8" 90 and then a reducer. From there on out I'm 6" and it drafts very well.

    I screwed the T into the EKO to secure it...three holes....
  14. verne

    verne Member

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    A 6" supervent or pro vent tee with cleanout fits tight .The outer of the doublewall fits outside the flange on the eko and the inside one fits inside. Cozy dave gave me the info. I purchased the tee from him and then used the pipe from lowes, Its about half the price and made by the same company with the same specs.
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