1. Welcome Hearth.com Guests and Visitors - Please enjoy our forums!
    Hearth.com GOLD Sponsors who help bring the site content to you:
    Hearthstone Soapstone and Cast-Iron stoves( Wood, Gas or Pellet Stoves and Inserts)
    Caluwe - Passion for Fire and Water ( Pellet and Wood Hydronic and Space Heating)

New to the forum, problem with Harmon Oakwood

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by Jim Barry, Feb 4, 2013.

  1. Jags

    Jags Moderate Moderator Staff Member

    Joined:
    Aug 2, 2006
    Messages:
    15,026
    Loc:
    Northern IL
    Yes - your slider is the adjustment for primary air. Basically the stove has two sources of air. Primary - adjustable and secondary - non adjustable (I assume the "firedome" design also requires secondary air like a tube re-burn).

    Helpful Sponsor Ads!





  2. Jim Barry

    Jim Barry New Member

    Joined:
    Feb 4, 2013
    Messages:
    18
    Loc:
    Loch Katrine, Nova Scotia
    So far as I know, this Oakwood stove has the primary damper up near the top, its either opened or closed. The other is the draft, which as discussed, is the front slider. I was told by the dealer that even when the draft is in the closed position (all the way to the left), the air intake is still 25% open. Designed to prevent total shut off of air flow.

    I've thought about your suggestion to disconnect the dedicated air intake. While willing to try that, I don't see the difference it will make. The stove will still be drawing air in from its 4" intake (located in the back lower part of the stove).

    I don't know anything about 'secondary air' or 'tube re-burn'. The stove is designed with a "secondary burn", if conditions are right, that does work.
  3. Jags

    Jags Moderate Moderator Staff Member

    Joined:
    Aug 2, 2006
    Messages:
    15,026
    Loc:
    Northern IL
    That stove has a proprietary reburn method that they call "fire dome" design. I hate to say it, but that is probably part of your problem. But I digress. The damper is the damper - no primary or whatever. As far as I understand it - it is to be used in a similar fashion to the bypass of a cat stove. The front slide is your combustion air (or commonly referred to as primary air in a normal tube designed stove).

    I have not spent any time with your specific stove or with the "fire dome" design for that matter, but if I understand the operation correctly you are supposed to bring the stove up to temp, use your damper to clamp down on the air circulation and force it into the "dome" and then adjust the combustion air to maintain a proper burn.

    Are you sure that the damper is working as designed?
    Are you sure that the combustion air slide is operating as designed?
    Pull the OAK to limit any possible air restrictions (for testing purposes).
    Try again.
  4. Jim Barry

    Jim Barry New Member

    Joined:
    Feb 4, 2013
    Messages:
    18
    Loc:
    Loch Katrine, Nova Scotia
    You are correct in its operation, at least that's how I also understand it. Seems straight forward.

    Damper is working so far as I know. The only problem is that when it is in the closed position, if a pressure drop occurs or if the stove whuffs, it will blow open the damper. That creates a dangerous situation of a run away fire, especailly if we are asleep or away from home. So we use a bungee cord to keep it closed. See attached. The handle is one I crafted after the factory one fell apart.

    The draft control (front slide mechanism) seems to be working fine. If its in the open position (positioned far right) and tehn closed (position far left), the fire will noticably fall.

    There are no air restrictions.

    Attached Files:

  5. Trilifter7

    Trilifter7 Feeling the Heat

    Joined:
    Oct 19, 2012
    Messages:
    452
    Loc:
    Beavercreek Ohio
    I still wonder if this is being caused by your setup. It looks like you meet all of the minimum clearances for the chimney height over the roof penetration and roof height, but I wonder if you are getting draft issues due to an air trap from your roof lines. Have you tried adding a few feet to the top of the chimney to get it up out of any possible wind traps or washing conditions? You could try this by adding a 2' or 3' piece of cheap single wall pipe to the top of the flu and see what happens. This could change the wind flow around your chimney and eliminate any possible disturbances in draft you might be getting. May not be the answer but might be worth trying.
  6. Nick Mystic

    Nick Mystic Minister of Fire

    Joined:
    Feb 12, 2013
    Messages:
    709
    Loc:
    Western North Carolina
    I agree with Jags suggestion of disconnecting the OAK to see how it burns using the indoor air from the room. Since the stove is acting like it is having trouble getting sufficient air while burning that's a good place to start by checking to make sure the OAK isn't blocked in some way or just not delivering the needed air. However, you say if you leave the damper closed and the air wide open you are getting a good burn, but going through wood faster than you think you should be. So that part is puzzling. I'd be interested to hear from some other Harmon stove owners to hear what their burn times are under similar parameters.
  7. Nick Mystic

    Nick Mystic Minister of Fire

    Joined:
    Feb 12, 2013
    Messages:
    709
    Loc:
    Western North Carolina
    In some of your videos it looks as though your single wall pipe connected to the top of your stove is installed upside down. The male ends of the pipe look to be pointing up with the female ends pointing down. It could just be an optical illusion in the videos, but if it is actually installed that way it makes me wonder about your professional installation. I wouldn't think this would have anything to do with your puffing problem, it's just an observation.
  8. MishMouse

    MishMouse Minister of Fire

    Joined:
    Jan 18, 2008
    Messages:
    782
    Loc:
    Verndale, MN
    I occasionally get the same type of explosions in my TL300 which uses the same combustion package as the Oakwood. But, when mine does it, no smoke
    is released. This only happens to me when I close the damper (which puts it into re-burn and directs the smoke/fire into the Firedome) before the stove gets over 450. Since the temp is low in the stove and the fire is not burning properly the FireDome ignites the gasses within the firebox instead of just in the AB chamber. This causes an abundance of gasses to accumulate in the firebox which then gets ignited causing the poof.

    Questions on how and when you close the damper:
    How hot is your stove before you close the damper?
    How is the fire burning lazy or rapidly?
    How hot is the chimney?
    Is the airwash system active when you close the damper?
    Do you get the typical jet engine roar from the FireDome as it shoots fire out of its airholes?
    Note: You should get the Jet engine sound after you close the damper and start turning down the primary air.

    Stove Questions:
    Has all your gaskets been checked, it seems strange that that much smoke would be released with one of the poofs.
    Has the FireDome package been checked?

    External Issues:
    Are you running anything else that could be causing you air flow issues creating negative pressure?
    Examples Hot water heater, additioanal heater like oil/gas, etc...

    Questions on your video:
    When you opened the door and your pipe smoked, was the damper open or closed?
    If I would do this with my TL300 smoke would come out the door, not the chimney.
    Is there a smell of smoke when the damper is open?
  9. Diabel

    Diabel Minister of Fire

    Joined:
    Jan 11, 2008
    Messages:
    882
    Loc:
    Ottawa, ON
    In one of the videos it appears that you just started the fire, the little split is just catching fire, and you close the damper! I don't think you could be anywhere close to 500* to light off the secondaries.
    Another thing I noticed in the same video, the fire is quite lazy and (just me thinking) if you are just starting the fire and everything is 100% open, that fire should be more lively....chimney set up could be an issue.
    Also, that little split is taking a while to catch fire.....you sure it is 14-18% moisture? Which brings me to another observation... When you pulled the cap off there was a lot of creo accumulated. Not sure what are your intervals between cleanings but that is quite a build up!! Again, me thinks...wood not quite there yet in terms of being prime for burning and likely smoldering fires due to closing damper too soon.
    These are just my thought and I am not an expert like several here.

    Ps I struggled with a downdraft stove for three seasons.....
  10. mellow

    mellow Resident Stove Connoisseur

    Joined:
    Jan 19, 2008
    Messages:
    3,191
    Loc:
    Salisbury, MD
    What I was going to say was already mentioned, add a piece of temporary single wall pipe to see if that helps with draft.

    Did the installer measure your draft to see if it is in spec?
  11. Diabel

    Diabel Minister of Fire

    Joined:
    Jan 11, 2008
    Messages:
    882
    Loc:
    Ottawa, ON
    +1 one the pipe extension! Cheap and quick draft test!

Share This Page