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Harman TL 300 Users

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by cyclone, Oct 5, 2008.

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  1. branchburner

    branchburner Minister of Fire

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    Yeah, you hit the nail on the head with this site - Harman refers everyone to the dealers and they are only rarely helpful, so that leaves this place - a great resource.
    I'm just getting statrted with the Oakwood and would say relax, everything I've heard indicates you won't get a good feel for all the ins and outs of these stove til the weather gets colder. Then you will have better draft, longer burns, less creosote, less soot, etc. I really even haven't tried for much secondary yet, but hope it's cold enough this weekend.
    For now just make sure you don't get the stove super hot. I measure temp on the stovetop, go up to 500 real quick, so I may need to check my gasket/seals. But even 600+ is not a prob, just not for extended periods.
    My big worry is my wife will throw a big load on and leave the air wide open and walk away! This isn't like the antique cooksove we had - it's a real burning MACHINE!

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  2. stanleyjohn

    stanleyjohn Feeling the Heat

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    [quote author="branchburner" date="1224321550

    My big worry is my wife will throw a big load on and leave the air wide open and walk away! This isn't like the antique cooksove we had - it's a real burning MACHINE![/quote]

    Hi honey! why is it so hot in here and what is that redish glow in the other room :lol:
  3. N/A N/A

    N/A N/A New Member

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    Also dont be afraid to try different things. If its not working for you dont be afraid to stick the poker in there and mix things up a bit. You will see that wood position does make a difference. At least from my experience so far. Also, if it didnt work the last time, try something new every time you fire the stove up. You guys with the downdraft type stoves will catch on. If I were you, I would not wait till the weather turns cold to figure the re-burn system out. But I guess its no big deal if your not heating with your stove full time like I am. If so figure it out now, before you need to rely on it. I have found that I can actually get more heat out of my stove letting it free burn rather than having the re-burn engaged.
  4. branchburner

    branchburner Minister of Fire

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    Tell us more about this...
  5. Seasoned Oak

    Seasoned Oak Minister of Fire

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    I read that minimum temp to burn smoke without a catalyst is 1100 degrees as in the TL-300 , with a cat stove smoke will burn at 500 degrees,but is dependent on other variables such as draft , so i guess thats why you have to get the harman good and hot in order to fire the afterburner.
  6. N/A N/A

    N/A N/A New Member

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    Letting the stove free burn I can easily let it get hot enough to melt into a puddle of steel on my floor. I can balance the stove top temp out at 600 degrees no problem. And thats hot! Once the re-burn is activated, the most I can get on the stove top is 500 degrees. When I get a good re-burn going the stove does not like the air all the way up for some reason. You would think the more air the hotter the fire. Not the case when using the secondary combustion. I have found that I get puff backs and stalls from to much air.
  7. MishMouse

    MishMouse Minister of Fire

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    Right now I rarely run it above the first notch when I put it into re-burn, anything above that right now would cook me out of house and home. But, one thing you will notice when the afterburn is engaged it puts out more heat at 500 when engaged then 650 when it is not engaged, especially if you are not using a blower. The reason, the afterburn chamber like a cat is magnifying the temp of the smoke causing it to be burnt. This puts out a heck of allot of heat.
    A Test you can try to see if it is working properly.

    Without running the blower hold your hand above the stove when you are getting the stove up to heat and see how long you can hold your hand there. Then when you place it into afterburn and cut the air down to the first notch put your hand over the same spot and feel the difference, especially when it is roaring.

    As for stalling when you have the air wide open in afterburn, (Which is something I would advise against) this is my guess to what is happening.
    First there are two ways air gets into the stove, is the primary air controlled by the little lever in front and the secondary air which is controlled by the stove itself. (Other people can probably explain the secondary air and back puffs allot better then I can :) ) When in afterburn you have to maintain a balance between the two, allowing enough air to enter the stove from the front while not over powering the downdraft which is maintaining the secondary combustion. When in afterburn your stove is much easier to control, holding a 400-500 stovetop temp while reburning the smoke is allot safer then a stove not in afterburn.

    I left the stove alone the other day when starting it and without putting it into afterburn I only had it between the first notch and the second notch, when I got back about 45 mins later it was above 700 stovetop. So if you go to bed without putting into afterburn you may just wake to a puddle of metal in the morning. A song by the Talking Heads comes to mind.... %-P
  8. stanleyjohn

    stanleyjohn Feeling the Heat

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    When you say first notch!is this with the air rod almost all the way in for min air flow?So far this season i have been running my stove from one half to two thirds in on the air flow rod.
  9. branchburner

    branchburner Minister of Fire

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    Puddle of steel is right! I can get the Oakwood from zero to sixty (600, that is) in about 10 minutes. If I give it more small stuff, even if I shut the air most or all the way, the thing is looking to go solar. Afterburn w/ no air is about my only option then (I have to re-check my gaskets - seems a bit too hot, too fast), or else a big split to slow it.
    But once the bypass is shut it settles into a long 550 burn, and its for sure throwing a more even heat than a 700 warmup fire. I don't just go by the stove top number. Yes, you do get a good hot blast at 600-700 w/ the damper open. But the thing about the afterburn in this stove is the heat is thrown a bit more from the back of the stove than the front and top, so you might be fooled at first. Just compare - burn a good long fire both ways and I think you may see, the serious, steady heat comes with afterburn engaged.
  10. Seasoned Oak

    Seasoned Oak Minister of Fire

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    Where is thew best place for the temp gauge, thinking about 1 just at the front of the flue pipe where it exits the stove and another magnetic on the middle of the top load door. Also when i am warming up the stove from cold the flue pipe just above the stove will start to get red if i use full air on front air control.
  11. Seasoned Oak

    Seasoned Oak Minister of Fire

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    I found out the hard way that if you do not have the stove hot enough and you engage the afterburner(and it does not fire) for an overnight burn, you will turn a full load of wood into creosote, mess up the whole inside of your stove, flue pipe and chimney, stink up the house and the neighborhood.
  12. branchburner

    branchburner Minister of Fire

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    I have mine on the middle of the top load door. I may get one for the flue - I've read it should be placed at least 12 inches up, which will be tough for me with my setup.

    You don't want red - that means you're pushing 1000. What's your stove temp when that happens?

    I find warming up the stove from cold with a good load of small stuff I need to shut down front air control very soon. My stove is drafting a little too good. Everyone is going to have different draft issues, so that will effect the timing and temps a good bit for each of us. Just a matter of adapting to your own setup and developing your own system for a good burn, which is gonna take time (I figure I'll know what I'm doing right about the time Spring arrives!).
  13. branchburner

    branchburner Minister of Fire

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    Righto! What are you burning besides that old lumber? That stuff should be great for getting up to temp (probably why you are glowing) but will not give you a coalbed. You need both before you can start a good long burn.
    I can get my stove to temp, 600+, in 10 min w/ dry scrap, but then need the better part of an hour w/ some bigger stuff to get enough coals for an afterburn.
  14. branchburner

    branchburner Minister of Fire

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    I would leave that oak you split this summer for another year, or even two. If you get some sizzle, your afterburn will fizzle. The heat you need to burn smoke will be spent boiling water.

    Oak is the best, but really needs time to dry out.
    If you don't have any drier wood, I would go tackle a few of those standing oaks before the snow flies! My experience w/ standing dead is you will still have some moisture, especially in the trunk portion, but will dry pretty quick.

    If I had those I would buck up the top halves of the trees for burning sooner, the bottom halves for burning later.
  15. Seasoned Oak

    Seasoned Oak Minister of Fire

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    Branchburner
    I have a lot of 3 year old hardwood,cut 3 years ago but i only split it 2 weeks ago ,still it seems pretty dry to me though. some of the old wood is oak also like T&G;floorboards, i dont think they would use soft wood for that. I usuall tell by the weight of the old wood,soft wood would be pretty light when is very dry and hard wood would be fairly heavy.Whats the deal with the deep coal bed ,is that to maintain high temp or what,if its too deep it will cover the front of the AB chamber.
  16. branchburner

    branchburner Minister of Fire

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    Yeah, if the 3-yr stuff was cut to length it should be pretty good - if it was log length maybe not. I've been using of hardwood pallet, like you old wood. I find it graet for getting the stove real hot real quick. It sound like it's maybe just a matter of adding gradually larger pieces til the afterburn wants to fire.

    I can't really explain the coal bed, but I think yes, to insure high temp. All I know is when it's there, my results are good. I don't think covering the base of the AB is a problem - I sort of recall reading that's it's a good thing to push the coals to the back, but don't quote me on that!

    I've found the search engine to be very helpful, even if the threads don't directly address my stove. A lot of the principles are the same on the VC downdrafts, for example, even if the actual burn methods differ. A lot of VC talk on this forum!
  17. Seasoned Oak

    Seasoned Oak Minister of Fire

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    Question for anyone monitoring temps on the tl-300. When the AB kicks in should it not have an immediate affect on the flue pipe temp as the flue pipe exits the stove just above the AB, would this not be a good way to judge if the AB is actually lit as sometimes it is covered by wood, and with coals piled up you can not see the opening directly ,and the only way i can think of (if there is no wooshing sound)to be sure the AB is working is by the stove temps. Some have posted that the stovetop(load door) temp falls to 450-500 when they close the damper, but would not the flue pipe temp actually rise? Just a thought.
  18. N/A N/A

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    Mine actually drops. When I first fire the stove up I let the pipe temp get up around 1000 degrees sometimes. And thats usually about 550 stove top. Sometimes with the re-burn it CAN drop to around 425 pipe or 350 stove top.
  19. N/A N/A

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    I dont think I totally agree with you guys. 600 is still warmer than 500 or 550. No matter how you look at it. $80 is not more money than $100. And I am not comparing efficiency or burn times. But at any given point in time with the numbers above the 600 degree stove is putting out more BTUs. Its obviously not going to burn as long with a given amount of wood but its still burning hotter. The difference might be that because the back of the stove is at temperature, you now have more surface area to transfer those BTUs from the stove to the room/air. Then again, from my temp numbers above, you can also take the stove pipe into account for both examples and include surface area to transfer heat. And the math to split hairs and actually figure this stuff out is a little above me right now. My collage days are far behind me and math was not my strong point. So maybe one of our member engineers would like to take a poke at it?
  20. Seasoned Oak

    Seasoned Oak Minister of Fire

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    Being that that the AB must be above 1100 degrees to light up and the flue pipe is directly above the AB would not the flue pipe be pretty hot when the AB is operating especially when most of the AB area is insulated with that refractory material and only the very top is exposed to the stove steel just under the flue pipe opening
  21. N/A N/A

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    Not exactly sure what your asking??? If you look at the TL 300 the pipe is split 50/50 darn close with the re burn package and the fire box. Just depends on what position the damper is in. But dont get it twisted, its still hot ether way. But in all seriousness, 1100 degrees is not really all that hot. With a normal fire in the fire box it is not unreasonable to think that areas in the fire box are 1100 degrees.
  22. MishMouse

    MishMouse Minister of Fire

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    Agreed 600 is warmer then 500, but when it is at 600 most of your heat is going up the flue.
    Also I wonder what the temp is over the after burn chamber when it is active.
    Since it magnifies the temp to re-burn the smoke, it has to be allot hotter inside then what is actually flowing up the flue when running it without the after burn engaged.

    Did you try the test and feel the top of the stove before and after?

    I wonder does anyone who have a TL-300 or an Oakwood for that matter have one of those digital light thermometers?
    I would like to find out what are the actual temps going on when you put it into after burn, like inside the stove itself, stove front etc..
    That would tell the real story.
  23. Seasoned Oak

    Seasoned Oak Minister of Fire

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    As per the flue pipe temp above the AB Im trying to come up with a formula to tell if the AB is lit up since you cant really see whats going on with a full load of wood in the stove. Im thinking that the stove temp may go down a little but the flue pipe temp should go up with the afterburner makng extremely hot fire out of the exhaust gas, thats why they need all that refractory material in there in the lower half of the AB and only near the flue pipe exit is there any bare steel to siphon some heat off the flue gas.
  24. branchburner

    branchburner Minister of Fire

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    Not sure if the cast Oakwood and the steel TL300 behave exactly the same, but I think you're on to something here. If the AB kicks in, I agree: I think you should see your stovetop temp drop and your flue temp rise.
    One way to find out - I'm picking up a second thermometer tomorrow!
    It was one of the first things I thought of when I got the thing cranking - man, I must be losing a few BTUs w/ the afterburn right in the back by the flue collar. Makes a good case for not having this stove set back in the fireplace like mine is.
  25. begreen

    begreen Mooderator Staff Member

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    Maybe so, keep us posted. If the stove is efficiently designed I would expect the opposite. That is, I'd want the heat exchange to be optimized so that when the AB kicks in, the stove starts radiating more heat and the flue temp drops. But perhaps that is not the case here.
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