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Duct Insulation

Post in 'The Pellet Mill - Pellet and Multifuel Stoves' started by Ejectr, Nov 10, 2012.

  1. Ejectr

    Ejectr Minister of Fire

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    I was going to cover my exit duct coming out of the top of my PF100 pellet furnace with foil faced duct insulation until I read on the Corning site that foil is flamable as well as the paper facing and must be kept away from even a hot electrical light by 3".

    I have a few areas where my duct comes within an inch or closer to the exhaust pipe on the furnace, which gives me cause for concern using this stuff. I can keep my hand on the exhaust pipe for quite awhile before I have to remove it and if the ESP is doing it's job, it shouldn't be over 165 degrees.

    So what say you gurus? Use it or not use it. It does have a fire rating on the MDS sheet.
    Thanks.
    http://www.homedepot.com/h_d1/N-5yc...ngId=-1&keyword=duct insulation&storeId=10051

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  2. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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    Remove the foil where the vent is or use a different insulation blanket where the vent is.
  3. Ejectr

    Ejectr Minister of Fire

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    Yes, I was thinking of doing that. I could use the Corning Eco Touch insulation so it wouldn't be detrimental to human contact.around the exhaust pipe area and use the foil type on the rest of it. Thanks.
  4. Ejectr

    Ejectr Minister of Fire

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    Can just the fiberglass insulation itself come in contact with the vent pipe at all? No foil or paper on it. Just the fiberglass wool itself. It is unfaced.

    There is no way I can insulate one area of the exit duct without it doing so. If not, I pretty good sized area will still be uninsulated along the bottom and one side that goes over the exhaust vent.
  5. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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    Fiberglass is considered noncombustible I don't see why it wouldn't be fine.
  6. Ejectr

    Ejectr Minister of Fire

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    Thanks. My cellar ceiling is uncommonly low and the existing duct work even lower, so the tin knocker had to go straight up and then a 90 degree turn over the exhaust pipe then a 90 degree turn to the trunk. I don't know why he didn't just have me move the furnace over more to the left and then go straight back, but he said that wouldn't have given him enough height to come straight out and a radius 90 degree bend turn to the trunk. So now the bottom of the left turn duct work is over the exhaust pipe. Had to use a clean out T and then a 45 degree to clear it with the vent pipe.

    It is what it is, so that's what I'll do. Thanks Smokey.
  7. Ejectr

    Ejectr Minister of Fire

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    Holey mackerel! What a difference the duct insulation made! Air coming out of heat registers is WAY warmer than before.
  8. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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    Make certain it can't burn the piggies...
  9. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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    Oh and you should discover a drop in the basement temps so pay attention to any plumbing down there.
  10. Ejectr

    Ejectr Minister of Fire

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    Still have plenty of radiation from the furnace itself heating the basement.. No worries about plumbing.
  11. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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    Ok, didn't want you to discover busted pipes or things.

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