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Load Started with Air completely closed

Post in 'The Hearth Room - Wood Stoves and Fireplaces' started by Huntindog1, Feb 6, 2013.

  1. Huntindog1

    Huntindog1 Minister of Fire

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    I can load good dry wood on hot bed of coals and shut the air completely down all the way.

    Yes for a few minutes the stove sits there and does nothing.

    I can come back later and the stove is roaring with the air complete shut and stove top temps are in the 700 to 800 range.

    I am thinking this is because with the air shut down all the way allows the stove to heat up easier with the hot coal bed. If the air is wide open or the door is cracked the air flow is much greater in the stove making it harder for heat to come up in the stove. With air shut the coals will heat the wood up and eventually take off and once it takes off the heat comes up in the stove very fast because there is such low air flow thru the stove. As wood burning is about the heat in the stove. I think we look more at burning causes heat but a better way to focus on it is the heat will allow the wood to burn as once the off gasing starts from the wood being heated up the burning will take off really fast. As the hot coal bed will be the source of the heat at the input air setting being completely closed and very little air flow allowing that coal bed to heat the wood much better.
    corey21 and Mitch Newton like this.

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  2. Huntindog1

    Huntindog1 Minister of Fire

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    I want to add the reason this is odd to me is that we think that if the stove is loaded such that it can over heat that we need to get the air shut down quicker to keep the stove under control. But in the example above the stove very quickly after flames start up goes to very high stove top temps. It does this with the air shut down completely from the get go. Odd in deed.
  3. Joful

    Joful Minister of Fire

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    I manage to forget to open the air on reload about once a month. Friends and family call me the absent-minded professor, so no surprise there. Yep, it always seems to take off just fine, although taking a little longer. The question is how much creosote you deposited in your chimney, while things were sitting there smoldering, prior to eventual take off.
  4. Huntindog1

    Huntindog1 Minister of Fire

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    Good Point, But thats where the dry wood comes in I dont think this can work with not so dry wood. So 5 minutes of no flame with dry wood would be very small amounts of creostoe formation if any.
  5. firebroad

    firebroad Minister of Fire

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    I wonder if your air controller is operating correctly?
    I have also had a fire start from just a few tiny coals while the vent was closed(or as much as closed as an EPA stove will allow), but in my case, it was a smokey, smouldering mess that didn't really contribute a lot of heat. Sounds like you are getting plenty of draft.
  6. peakbagger

    peakbagger Minister of Fire

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    I am nor familiar with the stove design but its doing what most EPA stoves are supposed to do, adding air through some hidden secondary system to ensure that the stove is not starved for air which is the major cause for stove pollution. It probably makes a big difference that you have dry wood.
  7. begreen

    begreen Mooderator Staff Member

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    It would work with our dry fir, but I like to rake the coal bed forward and burn it down a bit more. Then I reload E/W behind the now diminish coals with a couple small splits on the front hot coals. I give it full air to minimize smoke output from the chimney and turn it down as the fire gets going.
  8. corey21

    corey21 Minister of Fire

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    All wood when smoldered can gunk up your chimney dry or wet.
  9. Huntindog1

    Huntindog1 Minister of Fire

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    What I was really wanting to point out was the unique characteristics of this type startup , not really trying to persuade people to do it like this.

    But to say it in a different way is that on a hot bed of coals loading the stove up with good dry wood. With the air shut all the way down , one would think it would be a slow startup but its not, what I think happens is the hot coals will build up alot of heat and transfer that heat much quicker to the wood with the very low air flow thru the stove that normally would flush heat up the flue. We all think of wood burning as flame and we dont usually think of it in terms of heat. Coals have no flame but can have lots of heat. The air shut all the way lets the coal heat be more of a factor. What surprising that there is a delay in the fire starting but once it does the stove heats up much quicker. I think due to the nature of the startup being maybe a build up of wood gases and stove heat. ITs like at what point is the heat high enough to light off the wood gases. With the air wide open your flushing the smoke gases up the flue and your getting flames burning some but heating of the stove is slower due to the excess air flow ,thus thats why we shut the air down in increments to slow the flushing of the heat , thus building up more heat thus allowing the stove to burn at lower air settings due to the higher internal temps.

    Thats all a long winded explanation to say the stoves starts up in a much different way when the primary air is completely shut down with a hot bed of coals and a load of good dry wood. And its starts up and heats up in a way I would have never figured it would.
  10. DexterDay

    DexterDay Guest

    Not all stoves let in the same amounts of air when fully shut (all let some in).

    My 30 shuts down MUCH Further than my Uncles US Stove 2000. It's almost scary how much air is still coming through when shut down. So much so, that he doesn't need to open it much at all on a reload.

    So your VG may be letting in more air than other models. There is no set % on Primary air even when shut.

    Some let in more. Some less. Yours may be more.

    If I don't open my air, it's gonna smoulder. Unless, as BG stated, it's Good/Dry softwood And I am loading on a 500* stove top (which I don't do)
  11. Joful

    Joful Minister of Fire

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    Speaking of which, tonight was the night. Was in a rush to get both stoves reloaded and running this evening, having gone skiing with the 3-year old after work, and left the air control on the newer stove shut down all the way. She still started up, and in about the same amount of time as the older stove which had it's air wide open. The newer stove usually starts much quicker.
  12. ArsenalDon

    ArsenalDon Minister of Fire

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    Not every stove has an automated air controller...many if not most do not
  13. ArsenalDon

    ArsenalDon Minister of Fire

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    ditto
  14. rideau

    rideau Minister of Fire

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    I have a very strong draft. Last year Woodstock told me to start my stove that was...load her up, then close the air completely and engage the cat immediately, then just let it take it's time to start burning the smoke. Did this to be able to obtain a slow cat burn, instead of active secondaries. Worked just fine. I'm going to try it again now, to see if I can get my flue temps down.
  15. jdp1152

    jdp1152 Minister of Fire

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    On a hot coal bed, the fire is going long before I finish loading.
  16. topoftheriver

    topoftheriver Member

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    I have had simular situations and I don't believe the creosote build up with be that critical. Besides, once the fire is burning hot again, most of it should burn off. I can't fully explain why, but I don't build up that much creosote during a season anyway.
  17. firebroad

    firebroad Minister of Fire

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    This is a good thread, I have learned a lot. Interestingly, this I got up later than usual to a fairly cool stove, sifted out the coals to one side, shoveled the ash out; the coals were tiny, just a little glow but still hot. I figured I would test the theory, and loaded up the stove then went for coffee, etc. About ten minutes later, it looked like a fizzle out, then POOF! it ignited beautifully, all the time with the intake set as low as it could be. Had my wood been less than ideal, I doubt the same results would have happened. Interesting.
  18. velvetfoot

    velvetfoot Minister of Fire

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    Big smoke is probably coming out the stack when it's percolating.
    corey21 and Joful like this.
  19. BobUrban

    BobUrban Minister of Fire

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    My 30 has plenty of draft and I can open the door with air completely closed with no problems and quickly shut it all the way down after reload and it still gets going quickly with limited smoke and, yes, I have brain farted and loaded with air closed. Not often but it works. I typically realize my mistake because it is slow starting and just depends, as mentioned, on the coal bed and time I have before I need to get going.

    Once in a while when I am in a hurry I load and shut it down quicker than necessary. It may smoke a bit but always gets going and burns hot. Now that I have it dialed in with the wood I am burning I worry very little that it may go off to the races on a full load - even if I am not here to watch. Big loads stop climbing at around 6-650 and cruise for hours if I watch them or walk away.

    Now when I get to my oak stash in a couple years I will need to re-evaluate this!! I am burning 90% 2yr ash now with some maple mixed in.
  20. Huntindog1

    Huntindog1 Minister of Fire

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    I will also say that the wood is sitting on those hot coals with very little air flow. Most the air flow with the primary air shut completely is thru the secondary tubes in the top. I am thinking the air from the tubes quickly gets shunted up the flue as the tubes are in the top of the stove. When the primary air is open I would say air is moving in the bottom of the stove around the wood which keeps the wood from heating up as fast. With the primary air open you can have flames but maybe the wood isnt heating up as fast due to increased cooler air coming into the stove that is flowing around the wood surfaces. So this might explain for this unusual startup we are talking about. There is the small amount of dog house air but it seems to be coming into the stove at the coal level , i am thinking the dog house air is getting heated having to flow thru the hot coals. I see the wood getting heated in a more evenly manner then once the wood surface temps rise to the level that out gassing starts you have this really nice startup and fast heat up as the more evenly heat wood , all of the wood now starts out gassing at the same time providing more fuel for the secondary burn. As this is a feature of this start up is that once it happens the stove is really engulfed in a huge secondary burn in the top and stove temps increase much faster. The other way with air open the secondary burn has to like build up to a high level. I am not recommending this type start up but just that its an interesting type start up.
  21. rideau

    rideau Minister of Fire

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    I first get brightly shining coals, then wispy flames at the top of the box, then a gradual all over engulfment, then a good active burn with rolling secondaries. Started a fire like this last night around midnight, just a few logs. Loaded about 1/2 hour ago, after over 10 hours, onto a bed of coals from the back of the stove. Coals in the front had all burned down to ash.

    Load I justput in started active burn about 25 minutes into the burn, and secondaries are really firing now.
  22. pen

    pen There are some who call me...mod. Staff Member

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    Loading dry wood on hot coals means things are going to outgas. If the combustion air isn't there for that stuff to burn, you have a stove and chimney full of volatiles that are looking for an excuse to take off.

    Wind blows just right one day and draft increases for a split second, or you crack the door for some reason, etc, and more air is sucked in, and you can have a BOOM on your hands.

    Make sure you have 3 screws per stove joint.

    pen
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  23. rideau

    rideau Minister of Fire

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    I do have three screws.

    Woodstock told me to do this.

    The PH has an air opening in the lower front, which I always make sure is clear, as well as secondary air that gets in all the time.

    I've never had a "boom" or "poof" with this technique, although I have had one with regular loading technique. At the time I had it happen, I was NOT being careful about seeing that the lower air hole was unobstructed. I don't think you get the "poof" or "boom" when you keep that air intake open.

    i'm not suggesting others who don't have a PH try this technique. However, it is clearly a viable technique for the PH. I'm sure it varies from stove to stove.
  24. Huntindog1

    Huntindog1 Minister of Fire

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    50 deg outside last night sure has an efffect on my draw of my flue.
  25. Joful

    Joful Minister of Fire

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    I think you'll agree it's possible, though. Several Woodstock Progress Hybrid owners have already reported backpuffing in their stoves, and being a newer model, I'm assuming there aren't even that many of them out on the market yet.

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