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Getting an OAK for my Harman Accentra Insert

Post in 'The Pellet Mill - Pellet and Multifuel Stoves' started by tpme06, Aug 16, 2013.

  1. tpme06

    tpme06 New Member

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    I'm getting an OAK for my Harman Accentra insert this week. It is an open box item, so it doesn't have the instructions, so bear with me if this is addressed in them.

    I know I need a 3" pipe to run up the chimney, but I have some left over 4" pipe and was wondering if it would be problematic to use that? I'm going to get an exhaust adapter or some other metal fitting to retrofit the 4" pipe onto the 3" adapter. I'm assuming a bigger intake pipe won't have any negative effects? Please correct me if I'm wrong.

    Also, my chimney is probably 15 feet in length. My exhaust runs all the way up to the top (4" flexible pipe). Would it be okay if I ran the intake pipe 5 feet up? Or should it go higher? I'm not sure of the length I need for the OAK to perform as intended.

    Any insight and shared knowledge is greatly appreciated!

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  2. Delta-T

    Delta-T Minister of Fire

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    the 4" intake should pose no problems. Is the flashing on the top of your chimney vented somehow to allow for the intake to work, and/or are you using the Harman chimney extension apperatus thingy or something similar?
  3. tpme06

    tpme06 New Member

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    My chimney is open on top with a cap. The end of my exhaust pipe is wire tied to the mesh on the chimney cap at the very top.
  4. Delta-T

    Delta-T Minister of Fire

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    you have some type of block off plate installed near the damper? I will try to locate the instructions that go with that air intake part.

    edit: they only tell you how to bolt that part to the frame
  5. tpme06

    tpme06 New Member

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    I have insulation stuffed all around the damper, so just the 4" exhaust pipe is going to the top of the chimney at the moment. I'll make room in the insulation to fit the new 4" pipe through, allowing the air in the upper part of the chimney to be pulled into the stove. There should be enough of a draw to create air flow down into my chimney I'm assuming.
  6. Delta-T

    Delta-T Minister of Fire

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    according to manual, you must install a steel block off to run the intake in that configuration. Is Installation concept #1 in your manual. LIner running up a masonry chimney, capped to prevent rain/snow, steel block off at damper, insulation above block off is recommended. you'll see the intake poking just past the plate and insulation and you should be good. Without the fresh air you are not required to have the steel plate, with the fresh air you are. go figure.
  7. tpme06

    tpme06 New Member

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    Good call on that. Can't tell you how many times I've gone through the manual, yet failed to see that. Looks like I'll be building a block off plate! Also looks like I'll have no issues running the intake only up 5 ft or so, as that will clear the block off plate and make my install look just like the concept #1 you referenced. Thank you!
  8. Delta-T

    Delta-T Minister of Fire

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    no worries, I've read that thing about a million times....still had to look to make sure I knew what I was talking about. good luck.
  9. CtPaul

    CtPaul Burning Hunk

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  10. tpme06

    tpme06 New Member

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    Thanks for the post! Great info.

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