smoke from chimney at end of burns?

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dyerkutn

Feeling the Heat
Jul 11, 2011
289
Boston NW suburbs
This is picking up on a couple of posts from October but I don't know if people look back that far!

I have an Alderlea T-5--was installed in spring and have been trying to do this "shoulder season" burning efficiently but am inexperienced.

I can start it up pretty quickly, get the flue temp up and be without smoke from the chimney within 10 minutes. I get the air down as much as possible and run it for a while on two or three good sized splits .

I have been running in and out all day to see how the chimney does over the course of the burn. As the flue temp went to the "too low" section on the magnetic thermometer, smoke started coming out of the chimney--that was whether or not I gave it more air. At that point wood was still glowing, with intermittent flames. Now there is only coal type redness (although the splits have not completely fallen apart--and I can still produce a bit of flame if I increase the air) and no smoke from chimney.

So is it normal to have smoke at the tail end of a burn and is there a correlation between amount of smoke and creosote buildup?

I am trying to find a balance between efficiency and not making the place boiling hot.
 
The balance in shoulder season is also based on the outside temps and the amount of wood in the stove. Try smaller splits 3-4" splits for a hotter, shorter fire and and save the big boys for the full loads.
 
I get that too. And would bet most people do but it is on up before sunup and they just don't see it. The farther back the load burns the harder it is for primary air to get all the way to the back. But by that time in the load the moisture and nasties have already cooked out of all of the wood and chances of creosote production are really slim.
 
This is picking up on a couple of posts from October but I don't know if people look back that far!

I have an Alderlea T-5--was installed in spring and have been trying to do this "shoulder season" burning efficiently but am inexperienced.

I can start it up pretty quickly, get the flue temp up and be without smoke from the chimney within 10 minutes. I get the air down as much as possible and run it for a while on two or three good sized splits .

I have been running in and out all day to see how the chimney does over the course of the burn. As the flue temp went to the "too low" section on the magnetic thermometer, smoke started coming out of the chimney--that was whether or not I gave it more air. At that point wood was still glowing, with intermittent flames. Now there is only coal type redness (although the splits have not completely fallen apart--and I can still produce a bit of flame if I increase the air) and no smoke from chimney.

So is it normal to have smoke at the tail end of a burn and is there a correlation between amount of smoke and creosote buildup?

I am trying to find a balance between efficiency and not making the place boiling hot.

Rather than getting too hung up on if smoke is coming out of the chimney I'd pay more attention to the fire. Also you state you want to get the air down as much as possible. So, what does that describe? Do you want fire or do you want the stove to smoulder? Why not try keeping a fire going in the stove rather than the "wood still glowing?"

For later in the season, one trick we usually try to do is when the wood gets down to that stage where it is almost to the all coal stage, we open the draft full. This will cure those problems that folks will soon be asking on this forum because they are getting too many coals in the stove. Sooner or later folks get so many coals there isn't much room left for wood and it really hurts to read that some folks actually scoop out coals like they do ashes. There is a lot of heat in those coals and it makes sense to use that heat for your home.
 
ry smaller splits 3-4" splits for a hotter, shorter fire
begreen--thanks--that is actually what I have been doing---I guess I was misleading when I said good sized splits. The fires have been hot and short with long lasting coals--I have had nothing but coals for the last two hours and the place is steaming!! 43 degrees outside so not so cold. Feels great! My main concern was about smoke since no matter how big or small the fire, eventually the fire will burn down unless it is fed a lot--and from what I have read it is better to wait to put more wood on coals rather than when the fire is burning really hot. is that right?
 
That is right. Instead, burn down the coals a bit by opening up the air and raking them to the front and center of the stove.
 
I get that too
I assume you mean smoke???

And would bet most people do but it is on up before sunup and they just don't see it.
You mean in the case of their fire burning down to coals while they sleep?
he farther back the load burns the harder it is for primary air to get all the way to the back.
not sure what you mean. Is this because the primary air comes in from the front? I think the control level on the T5 controls air intake from a front and back opening simultaneously.

But by that time in the load the moisture and nasties have already cooked out of all of the wood and chances of creosote production are really slim.
So even if there is some smoke it probably does not contain creosote. Also, I think my wood is pretty dry because it chars up within a couple of minutes of being put on coals.
 
The primary air feed the air wash over the glass and to the front base of the fire. Also, there is a boost manifold that supplies extra air front and center.
 
when the wood gets down to that stage where it is almost to the all coal stage, we open the draft full.
Thanks for this--BeGreen gave me the same advice. I thought if I opened the air all the way the coals would completely burn out and nothing would be left to start the fire.

By the way--scoop out the coals--never!!! they are keeping my house really toasty even now, several hours after I put in the last pieces of wood. Thanks for your help. This is really exciting making the switch over to total wood and having this forum for advice is really helpful, even though I know there is some experimentation involved.
 
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I assume you mean smoke??? Yep.


You mean in the case of their fire burning down to coals while they sleep? Yep.

not sure what you mean. Is this because the primary air comes in from the front? I think the control level on the T5 controls air intake from a front and back opening simultaneously. Air comes into the T-5 from the front.


So even if there is some smoke it probably does not contain creosote. Yep.
 
Well Is the T-5 a cat stove?
If not once the secondary's are out you are likely to get some smoke.
 
When I had a non cat if I was around I opened the air up some at the end of the burn. It helped burn down the coals and would stop the little bit of smoke I would get.

I think it is a non cat thing. You have to dial them down enough so they don't run away early in the burn due to the unregulated secondary air then at the end of the burn you're not left with enough primary air to burn whats left in the back of the stove as clean as you'd like.
 
Sooner or later folks get so many coals there isn't much room left for wood and it really hurts to read that some folks actually scoop out coals like they do ashes. There is a lot of heat in those coals and it makes sense to use that heat for your home.

Yes there is a lot of heat there. Thing is when you need more heat, when it's real cold, and you don't want your backup heat to kick on, there really is no alternative to reclaiming space for more firewood at times than moving out some of the coals. Of course as frugal as I am, there's no way I'm about to discard them. I put them in the covered ash bucket, on a noncombustible floor like the hearth -- (in my house sitting on an on-grade concrete slab, that's just about any non-carpeted floor) and reclaim the heat from the hot metal bucket, (being tightly covered, fire dies out quickly with no smoke escaping). Then later, the coals come in handy to augment a new fire.

Actually, I think I'm going to have to pick up an additional covered ash bucket, and reserve it just for coals to recycle.
 
Yes there is a lot of heat there. Thing is when you need more heat, when it's real cold, and you don't want your backup heat to kick on, there really is no alternative to reclaiming space for more firewood at times than moving out some of the coals. Of course as frugal as I am, there's no way I'm about to discard them. I put them in the covered ash bucket, on a noncombustible floor like the hearth -- (in my house sitting on an on-grade concrete slab, that's just about any non-carpeted floor) and reclaim the heat from the hot metal bucket, (being tightly covered, fire dies out quickly with no smoke escaping). Then later, the coals come in handy to augment a new fire.

Actually, I think I'm going to have to pick up an additional covered ash bucket, and reserve it just for coals to recycle.

Yes, there is an alternative!

When we got our last stove, a cat stove and an epa stove, we too suddenly learned that coaling can be a problem. Like you, we needed more heat because it was very cold outdoors. I looked around for some help but found none so just simply thought it over and did what I thought would work and fortunately, it did. If it had not worked, then we would have been like you with needing more heat because it was really cold outside. We've never had that problem since.
 
Pulling the pile of coals as far forward as you can and putting a small split on top with the air open takes care of the heat requirement just fine. Burns down the mass of coals while the blazing spit kicks a bunch of heat. In fact if I see too large a coal bed coming for setting up the night burn that is how I knock'em down.

Ain't never taken a coal out of the stove on purpose in my life.
 
I was curious about this too, as I have noticed it with my NC-30. Smoky on reload, burns with none/barely visible smoke during the secondary burn and for 1-3 hours after that, depending on the load size, then I get smoke through the last few hours of the burn. Glad this is standard operating procedure for this stove.
 
One thing is to leave the primary air a little open throughout the burn instead of closing it all the way down. I don't know where all of the "Get it blasting and shut it all the way down." comes from all the time. I never shut primary air all the way down.
 
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I never shut mine all the way either. My draft isn't the strongest, so I rarely close the primary air more than 75 or 80 percent of the way. That seems to be plenty closed down to get great secondary action.
 
Well Is the T-5 a cat stove?
If not once the secondary's are out you are likely to get some smoke.
Not at the end of the burn usually, at that point of the burn cycle the gases are gone, even my old stove does not smoke at the end of the burn if I open up the air and rake the coals forward.
 
Not at the end of the burn usually, at that point of the burn cycle the gases are gone, even my old stove does not smoke at the end of the burn if I open up the air and rake the coals forward.
I was just saying after the secondary's go out there can be smoke.
You need around 1000 degrees f in the box for those to work while a cat stove will keep the smoke away as low as 500.
 
I was just saying after the secondary's go out there can be smoke.
You need around 1000 degrees f in the box for those to work while a cat stove will keep the smoke away as low as 500.

A crock. The cat stove surface temp needs to be five hundred. Just like a non-cat needs for secondary burn. When either one is at 500 the firebox temp is around 1,000.
 
A crock. The cat stove surface temp needs to be five hundred. Just like a non-cat needs for secondary burn. When either one is at 500 the firebox temp is around 1,000.

Not true, my cat lights off at a stove top temp around 250. A 250 stove top temp is usually close to a 500 cat temp.
 
A crock. The cat stove surface temp needs to be five hundred. Just like a non-cat needs for secondary burn. When either one is at 500 the firebox temp is around 1,000.
Well hopefully we can agree to disagree on that.
Flame won't happen till around 1000 degrees f on a tube secondary.
A cat will still eat smoke at 500f..maybe 250 stove top temp above cat.
 
"The charcoal glows: As the fire progresses and most of the gases and tars have vaporized out of the wood, charcoal remains. Charcoal is almost pure carbon and burns with a red glow and very little flame or smoke. Charcoal is a good fuel that burns easily and cleanly if it is given enough air. Although charcoal combustion produces almost no smoke, the exhaust can have high concentrations of carbon monoxide, so it must be vented completely to outdoors."
Burning a stove clean is more then just the stove.
 
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