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Enviro Mini - Sorry - But Yet Another OAK (Outside Air Kit) Question

Post in 'The Pellet Mill - Pellet and Multifuel Stoves' started by LI-Mini-Owner, Feb 14, 2010.

  1. DexterDay

    DexterDay Guest

    I have an OAK on mine. I did a pretty good job sealing all holes, and cracks in my system.

    Even if you don't, the air will take the path of least resistance. It would rather come in that 3" vent that's a few inches away from the intake source, than come in through your bedroom window 35' away. IMO.

    OAK's always help....

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  2. Don2222

    Don2222 Minister of Fire

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    Most OAKs take cold and sometimes damp air from the outside which unfortunately reduce the overall efficiency of the pellet heater. It's like putting damp and cold wood into a wood stove!

    The absolute best solution is to pre-heat that outside air to make it warm and keep it dry with Selkirk DT venting that I install.

    see pic below

    Attached Files:

  3. LI-Mini-Owner

    LI-Mini-Owner Member

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    I replaced my vent/thimble this year because I had the house re-sided. I installed a Simpson Duravent thimble with a build in OAK. Even though it doesn't terminate at the burn pot, at least I know the stove isn't competing for air.
  4. Enviro Mini Owner

    Enviro Mini Owner New Member

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    I went ahead and had an OAK installed. Even though it is not a perfect connection as detailed above, it has allowed me to leave the forced air vents from the gas furnace open that were the stoves source for air, dragging the cold basement air up into the house. Everyone of them, we live in a small cottage, was a torrent of air.
  5. DBCOOPER

    DBCOOPER Feeling the Heat

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    Are you saying that preheating the air drys it? Where does the moisture go?
  6. jhanan

    jhanan New Member

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    Thanks, this answer some of my questions about the OAK connection on the Mini I'm installing right now. I also though it was missing parts to the burn box. Now, what about the large air intake hole between the draft slider and the combustion fan. That is strange design to me as well. I guess the design mixes house air with exhaust air on right before the combustion fan. I guess the design is like the air max flapper on my furnace exhaust ducting.
  7. chickenman

    chickenman Minister of Fire

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    Here! Here!
  8. jhanan

    jhanan New Member

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    Also it looks like my stove arrived with the "with the little flapping door" missing!!! Will have call dealer on Monday. Is the door optional. Thinking about making a temporary solution. The door is to the fan box where that vacuum sensor hose terminates.
  9. jhanan

    jhanan New Member

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  10. bob bare

    bob bare Minister of Fire

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    Before you jump on the"fake OAK" bandwagon,Realize a lot of european stoves were/are made this way,some american stoves have bleed holes(shudder everytime someone writes they taped/blocked them).Cold air reduces availible heat,hence the design of your stoves pipe system,same as a bixby.There also may be safety reasons for these designs,as something bad could happen with total air blockage.
  11. hockeypuck

    hockeypuck Feeling the Heat

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    I would be afraid of voiding any warranties by doing this. The enviro, like many other stoves, do not direct the outside air into the air intake port. Why they want to mix inside air is anyone's guess. Could be safety reasons... ie the oak gets blocked or it also could be they want to blend the cold air with warmer air before combustion. "Gerryrigging" your own thoughts on what an OAK should be could be dangerous. This is one of the reasons why I do not feel the urge to install the OAK. Until I figure a way to install some sort of automatic damper to open and close the air supply, I will not be using one. My stove does not run 24/7, so why would I want cold air pouring into my room. I have enough leaking window that already does this.. I do not need any more drafts.
  12. bob bare

    bob bare Minister of Fire

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    Good to see some common sense.Appears some people did not pay attention in school.One reason for a blended system is in case of house depressurization,smoke does not get drawn into house as bad.Do not have an oak as I shut stove off during day a lot,and run it on low a lot,however adding a water valve to a oak would be easy.European stove installers sell oak sets with a simple shutoff made in pipe,if you are interested. http://www.woodheat.org/the-outdoor-air-myth-exposed.html
  13. jhanan

    jhanan New Member

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    The design does not make sense. My US Stove OAK is a direct connect to the outside so there is no cold air dumping into the room.
  14. jhanan

    jhanan New Member

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    Pellet stove is a forced air system - so does this apply? Anyway - a value would be must and you have to now remember to turn it on and off.
  15. bob bare

    bob bare Minister of Fire

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    What part not apply?Also,most of the rest of the world does not waste heat the way we do,so walking over and shutting a valve is nothing to them.(heat costs lots more for them)
  16. batchman

    batchman New Member

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    On my Maxx, I found I was getting very little draft through the OA pipe. I removed the backdraft flapper and it improved enough to at least hold a piece of paper over the open end of the pipe - but not even dimple it. I'm starting to think about a vacuum controlled flapper valve in the OAK.

    I think too much.

    Cheers,
    - Jeff
  17. bob bare

    bob bare Minister of Fire

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    Actually good idea.
  18. chickenman

    chickenman Minister of Fire

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    There is only one reason why all stoves do not come with a sealed system, heat exchanging OAK. Cost.
    Manufacturers can give you all kinds of crazy reasons but it all comes down to the fact that it is more expensive to design and build. They are just saving money, the rest is nonsense.
  19. bob bare

    bob bare Minister of Fire

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    We can agree to disagree.But why do some stoves that oak is directed to firebox have holes drilled and a stopper flange so they cannot be covered?I think engineers know more than us.
  20. chickenman

    chickenman Minister of Fire

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    It is simple Bob. THe air temp from a standard oak is too low for start up and in the case of cold climes like yours for running as well. The expensive way around this problem is the heat exchanging flue. The cheap and easy fix is drill a few holes or leave a gap in the pipe, like the pictures shown.
    Don't forget that engineers work within the brief they are given. During my time in industry that brief was always; make it work for the lowest price. That approach does not inspire product development.
  21. bob bare

    bob bare Minister of Fire

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    Thanks for reply.I see you,me and don agree preheated air is better for combustion,especially in colder weather.As my unit is old,that would make sense,and I have heard enviros had wind problems,so that was their fix.You do know you are going to make some people mad with that "running in cold climate" statement!!!! By the way,montana is generally way warmer than the upper mid west(michigan,etc) just cooler weather lasts longer out here.Lots of days stove only runs a few hours.
  22. chickenman

    chickenman Minister of Fire

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    I hope people aren't offended by the cold weather statement. I am talking from the point of view of an Australian. All of the US looks cold to me.
    We simply have no concept of the crappy weather you endure. Less than 30 degrees F is unheard of here and even in the depth of winter minimum day time temp is 50 F. Top today of 95F. Yuck!
  23. bob bare

    bob bare Minister of Fire

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    What I meant was there are a lot of oak people that think it makes all stoves run better,all weather,all oak configurations.But in the last 2 weeks it has been anywhere from -30 to 50,but I am in the mountains,6500',most people live in the valleys.
  24. chickenman

    chickenman Minister of Fire

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    Fair enough. Yeah an unwarmed oak would be a liability in air temps lower than 38F.
    Just a question; how do you get the stoves to run right in high altitudes? WE have some alpine located stoves and they really struggle. I think it must have something to do with the thinner air or something. It may also be limitation of multi-fuel compared to pellets?
  25. bob bare

    bob bare Minister of Fire

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    Do some research,i run an austroflamm,has a mass air flow sensor(bmw)was specifically designed to run at all altutides.Some of the Italian stoves use this system now,so suppose they would work.Have worked on other stoves at higher altitudes,usually have to bypass vacuum sensor(older ones) but if had pressure sensor was ok(some whitfields.etc)Best to have short exhaust when going higher in mountains.This is just my experiences,auto mechanic by trade.Best way to approach problem(altutide)is speed up combustion blower.Need more volume for same o2 content.

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