Going down from 7" flue to 6" Piping on Kitchen Queen Cookstove?

Discussion in 'Homesteading Questions' started by mommykood, Feb 4, 2005.

  1. mommykood

    mommykood Active Member

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    We have ordered a Kitchen Queen cookstove, and I am wondering if I can use 6" piping for from the stove flue up through the raincap. The flue for the Kitchen Queen is 7", however. We will be using double wall stove pipe, and insulated chimney piping outside the house.

    We plan to run the double wall stove piping straight up (we have 8' walls in the great room), and then turn the piping 90 degrees, to exit the wall of the house. We will then run the insulated chimney piping straight up, along side the outside of the house. The insulated chimney piping will run past the 4' side walls of the 2nd floor (it is a loft area), and end up passing the roofline (4' more).

    Is there any reason we can not use a reducer on the flue to go from 7" down to 6" piping? If so, what are the reasons?

    Also, anyone know a reasonable place to get 7" piping? It would be double-wall stove pipe, and insulated chimney pipe.

    Thanks SO much for the advice!

    Jen :)
     
  2. Cabin Fever

    Cabin Fever Life NRA Member since 1976 Supporter

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    You never want to reduce the size of stovepipe and chimney pipe from what the manufacturer recommends. If you can't find 7" pipe (which I have never heard of), then go with 8".

    The recommended diameter of stove and chimney pipe has nothing to do with the size or type of woodburning applicance. The size of the pipe is based on the size of door opening. The larger the door, the larger the recommended pipe diameter. WHat this means is, if you do decide to use 6" pipe, it will work except that every time you open the door to feed the fire, smoke is likely to belch out into the room.
     

  3. MorrisonCorner

    MorrisonCorner Mansfield, VT for 200 yrs

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    Further info: we installed a stove with a big pipe into a smaller one for the chimney, and the person who came to clean it actually blanched. Apparently this is a house fire waiting to happen. You NEVER go "big to little." It doesn't draw right and when (not if) the chimney fire happens it apparently shoots in both directions, out the top of the stack and into the house.

    Not good.
     
  4. uncle Will in In.

    uncle Will in In. Well-Known Member Supporter

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    About all the old cookstoves and heating stoves I've seen were fitted with six inch stove pipe. They mostly were hooked to an unlined brick chimney. Many of them had a seven inch oval cast pipe on the stove to connect a reducer section of steel stove pipe. These reducer sections were available at most hdwe. stores.
     
  5. Bob_W_in_NM

    Bob_W_in_NM Well-Known Member

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    I'll agree with the school of thought that says "go bigger, not smaller". I would hate to reduce the pipe to six inches if it was just a straight run up from the stove and out the roof. You're talking about having two 90 degree bends in it.

    I never saw any 7 inch stove pipe. Just 6 inch and 8 inch. Either the stove manufacturer or the pipe manufacturer should offer an adapter to go from the stove to 8 inch pipe.

    I would really go to the trouble to do this right if I were you. If something goes awry, it may not just be an "inconveinience", but could cost you and your family
    your lives.

    The short run of pipe mentioned going into a brick chimney might work. There's a lot more potential for "draft" in that case. But, I take it you don't have a chimney, at least where the stove is located, so it's a moot point anyway.
     
  6. .netDude

    .netDude Well-Known Member

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    Tagging a new question onto the thread...
    The house I'm going to move into has a gas furnace piped to an unlined chimney. There used to be a woodstove being vented to that chimney (before the gas furnace.) My question is, can I pipe a wood stove into that chimney again? If not, could I drop stove pipe down the inside of the chimney?
    Thanks -Greg
     
  7. big rockpile

    big rockpile If I need a Shelter

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    I was always told not to run Wood stove pipe into a Brick Flue that has had Gas vented into it.You could Line it.

    big rockpile
     
  8. uncle Will in In.

    uncle Will in In. Well-Known Member Supporter

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    Rocky is right about not hooking a wood stove in the same flue with a gas furnace. If creosote plugs the chimney, you will wake up dead.
    If the brick chimney is in good condition, I would consider putting a metal chimney on the gas furnace, and hooking the woodstove to the brick chimney.
    However if the bricks have mortar cracks between some of them, that would create a fire hazard.
     
  9. rambler

    rambler Well-Known Member Supporter

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    Just to add to the pot:

    You are creating a dangerous situation by reducing the flu size. At the least it will give you puffy smoke into the house. Could be a lot worse.

    Lots of stoves I looked at had 7" outputs. I believe they run into an 8" chimney most of the time.


    Also, you cannot mix gas appliances & anything else. Again for safety & health & burning the house down. Not allowed! And a bad idea.

    In today's world they don't allow mixing solid fuel & liquid fuel exhausts either, but there is less good science for this. That would mean, you can't plumb a wood stove & a furnace fuel stove into the same chimney under today's code.

    --->Paul
     
  10. .netDude

    .netDude Well-Known Member

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    mommykood, sorry for tagging onto the thread.

    To the respondants of my question, I want to take the gas furnace out (it's not the primary furnace, only heats a couple rooms), and replace it with a wood stove.
    Sorry for not being clear about that...
     
  11. SRSLADE

    SRSLADE Well-Known Member

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    If you are talking about a 7 inch oval hole on top of the stove. This does reduce down to 6 inch in one pipe made for this purpose. steve
     
  12. coldfront

    coldfront New Member

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    In today's world they don't allow mixing solid fuel & liquid fuel exhausts either, but there is less good science for this. That would mean, you can't plumb a wood stove & a furnace fuel stove into the same chimney under today's code.


    I just bought a house in upstate new york and the furnace and wood stove utilize the same metal chimney. So i guess i better check it out with the local codes. I talked to the previous owner and he said he has been running it like that for 10 years.
     
  13. rambler

    rambler Well-Known Member Supporter

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    You likely are grandfathered in, but if either furnace needs replacing you would need to figure something else out.

    --->Paul