I'm curious if it is possible for a chimney to be smokeless, but for combustion to be incomplete- or if they are mutually exclusive. Looking to geek out a little on the specifics of efficiency, pollution, and the visible indicators of such. I'm imagining that it might be possible for a stove to have so much draft (say ashpan door left open) that many of the volatile gasses escape before getting burned, but that the chimney is still smokeless. Is that possible? Full disclosure I'm trying to win an argument with my house mate who insists on leaving the ashpan door open until the stove top thermometer reaches the "good burn" line. For him it's all about the pollution. For me it's about stove longevity and burning less wood (which equals less pollution). I would love some good science on this one because he does listen to reason.
Is a smokeless chimney an indication of no unburnt gasses escaping?
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First welcome to hearth Hearthwood.
Second -
NEVER LEAVE THE ASH PAN DOOR OPEN It can cause a rather large fire ball explosion out the chimney and possibly a chimney fire. I am assuming your using an EPA stove ? EPA stove that are tube use air through the back up to the top inside of the stove which burns off the gases and makes your stove burn clean using air tubes. On initial fire up there is smoke for a few minutes when done right but will clear up and look like gas vapor without smoke. You will pollute less if you run the stove the way it was intended which means do not leave the ash door open it is dangerous ! Smack your room mate upside the head for me then wish him a merry christmas
.Merry Christmas
Pete
PS watch this vid it will help him not burn the house down and kill himself and you !
Thanks pete, yes I smack him upside the head regularly! That didn't work so I figured I'd resort to science. As far as the air tubes for the secondary burning, apparently they only work when the air coming out of them is heated enough to not reduce the temperature of the oxygen starved volatile gases below 1200 deg when they won't ignite any more. And apparently it takes a really hot fire box to heat the incoming air that fast. I've figured out what it looks like when secondary burning occurs and it's amazing how fickle it is unless i have a really hot stove. Nice to be here!
HotCoals
Minister of Fire
Sounds like you have a good grip on things.
Now replace that tube stove for a cat and all will be good!
Just joking! lol
The first and foremost issue should be safety; I'm not aware of any wood stove manufacturer that not warn against running the stove with the ash pan door open. The stovetop and stack temperatures should be monitored and maintained also within prescribed safe limits. What happens when you exceed this by turning your stove into a forge is beyond my guess. As you noted, secondary burn requires the fire box to be above a certain temp and the speed of the gasses and particulate matter need to be slow enough for re-burn to occur in the fire box. The velocity of the gasses when the ash is open should prevent max secondary bun in the fire box; which slows stovetop heating.
What kind of stove do you have ? I have been heating with wood a long time and in my personal experience less air equals much more heat in the box. The reason for this is the more air you let in the quicker it goes up the chimney. The secondary works even if you don't see it go outside and look at the chimney if there is no smoke the secondary are working. You are severely underestimating your stove or the install is not done right. From the sound of it your stove does not have enough draft because you should never need to open the ash pan door to get the secondary going. Can you put up pics of the install as well as chimney height and specs. With my stove it takes about 15 minutes from a fresh load of wood without kindling to get the secondary going and then I just walk the air down. 5 minutes with the door open to get a good fire and then close it another 10 and the secondary is going with no smoke. I would hate to see you have a fire !
Pete
By the way we are not trying to scare you off just help so don't be intimidated by us bossy hearthers but please do listen as we have a lot of combined knowledge here. You did a great thing by coming here now we can all nit pick your set up apart .
Pete
.Pete
Thanks Pete, the real issue is him not using kindling and the wood being just south of perfectly seasoned. Also having a small firebox so less room to muck around with lighting techniques. The ash pan door method is how he uses the "forge" technique to get paper (egg carton) to light logs. We each have a jotul F3, each in our respective places, so we each get to do it our own way. I used to do that because it was easier than making kindling but started learning how heating the metal up so quickly could lead to cracking or other issues over time. I never left it unattended for the few minutes I left it open (neither does he) because I'm pretty aware of the consequences of over heating a stove or getting flame up into a creosote coated pipe (being a rural volunteer fire fighter). But now I'm procrastinating my Christmas cards, I can see how this forum thing can become addicting. It's nice to be able to access such wisdom at my finger tips. Merry Christmas!
Another issue is dry wood what a dealer sells you and says is dry is NOT dry wood. Wood needs to be spits tacked and dryed for at least 1 year in the wind 2 if possible. A dealer will say 6 months or even 2 years however it is in log form they are talkin about not split. Logs retain the moisture for a very long time if they are not split. I have only encountered one wood dealer that has been honest and that was because he was not a big time seller only as he cut it.that is not to say everyoneis this way but the vast majority are so be carefull. This means when you burn it will not lite easily and the stove will have to be stupid hot to get the secondary's going at all. When you burn wet wood it takes all of its energy to dry it inside of the stove and won't throw good heat out and by the time the wood is dry there is not enough left to work with.
Pete
Pete
Haha I just typed up the wood thing while you typed up the wood thing HAHAHAHAHA.
Pete
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