The color of smoke

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cmonSTART

Minister of Fire
I'm curious. Usually with our new stove, the chimney just puts out clear, or very very thin whitish smoke mixed in with the heat waves. Sometimes after I reload it's a bit thicker, but always whitish or very light gray. My neighbor across the street runs an old smoke dragon and his is always very thick, solid white/gray. I've heard of gray, black and other colors. What do these different colors mean? Do these different colors tell us different things about how our stoves are burning at those times?
 
Not too sure, but the experts will be along shortly to answer your question. Although the smoke needs to be black to name a new POPE. BadddaBing
 
An inefficient burn will produce smoke with a blueish tint to it. White stuff coming out that rises and disappears in ten or twenty feet is steam from moisture in the wood and the intake air.

Black smoke means that somebody is burning old tires in their stove.
 
What about the stink coming out of a chimney? the guy next door has one really smokey woodstove, I know he burns wet/unseasoned wood along with pallets and probably all the paper he uses. It smokes like a b*st*rd, white and blue but mostly it stinks. Now the guy down the block just moved in, the people before him did not use the woodstove, he fired it up the other day, blue smoke but it didn't stink, smelled nice actually.

I guess what this comes down to is my indecision to buy a woodstove, I was all set to buy a Quad 3100 but got cold feet based on smokey joe next door's wood stove. The lady on the other side of me (downwind) has emphysema and b*thches about the other guys wood stove, but I'm thinking if I install a good wood stove burning well with good wood that I won't put out smoke and/or stink to bother anyone. I'm also concerned that my chimney exhaust will settle and stain her new metal roof, is that just being paranoid? I need someone to sway me in one direction or another, the wife just says do "whatever you want". I want to heat with wood but don't want to be a bad neighbor either.
 
All I can say is here are my Englander and Jotul F100's stacks 40 minutes after I fired them up a couple of weeks ago.

I burn five cords a year and last year my neighbor asked me if I ever burn wood.
 

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BrotherBart said:
All I can say is here are my Englander and Jotul F100's stacks 40 minutes after I fired them up a couple of weeks ago.

I burn five cords a year and last year my neighbor asked me if I ever burn wood.
BB, you have beautiful exhaust!
 
jpl1nh said:
BrotherBart said:
All I can say is here are my Englander and Jotul F100's stacks 40 minutes after I fired them up a couple of weeks ago.

I burn five cords a year and last year my neighbor asked me if I ever burn wood.
BB, you have beautiful exhaust!

This summer I fired up the meat smoker and the wind shifted and completely engulfed that neighbor's house in smoke for hours.
 
I'm curious too about odor. When my PE is burning well, not only is the smoke hard to see (forget seeing it against a blue sky), it doesn't smell like typical wood stove smoke. It's been a while since I burned coal, but from what I remember, the odor is more like coal than wood! Anybody else notice this?
 
Some people with old dragons burn their household garbage, especially if they have to pay for sanitation services.

It just isn't right but little we can do about it.
 
N1ST said:
I'm curious too about odor. When my PE is burning well, not only is the smoke hard to see (forget seeing it against a blue sky), it doesn't smell like typical wood stove smoke. It's been a while since I burned coal, but from what I remember, the odor is more like coal than wood! Anybody else notice this?
Absolutely! The one drawback to my cat stove is there is non of that "mmm...wood smoke" smell. Instead what little odor there is is more like car exhaust if there is any odor at all. I credit that to the nearly complet combustion taking place.
 
N1ST said:
I'm curious too about odor. When my PE is burning well, not only is the smoke hard to see (forget seeing it against a blue sky), it doesn't smell like typical wood stove smoke. It's been a while since I burned coal, but from what I remember, the odor is more like coal than wood! Anybody else notice this?

Yeah. All of that lovely smoke we used to smell is getting incinerated up at the top of the firebox before it goes up the stack. Just leaves the smell of burned carbon like the coal does. Same smell when you open the stove door while it is burning.
 
BrotherBart,

Thanks for the Pic! I downloaded and watched the video of the guy and girl in Canada building and burning a fire with no emissions.

It would be cool to see some pics of chimneys during start up, burning along and then restarting the fire from coals so newbs like me self have a base line for what (or what not) one should see coming out of the chimney. I know it depends on the stove and wood and etc., but without opening a can of worms, I think it would help. It would help me at least.
 
You know the smell is something I didn't understand until you guys mentioned it. As a kid we had a fireplace and when we were outside and it was burning, you could clearly see the smoke and smell the wood smell. With the Summit, I rarely see any smoke. I do smell the smell from it and I thought, wow that wood smells like s%^t. Now I realize it's not a smokey wood smell. I thought it was just the type of wood I was burning.
 
Speaking of smoke or should I say no smoke.
I went out to peak at my chimney before I going to bed, per my usual.
Well, I must not of closed my back door tight enough.
I woke up cold, very cold, my door was open about a foot wide.
The upstairs was still warm since all that cold air pushed it up.
DOUH!
 
I must have a weird stove when it comes to smell. I smell nothing untill my stove gets up to around 600+ degrees. Then i get this really sweet pleasant smell. No idea what it is. Its a great way of letting me know that the stove is up to temp though.
 
cmonSTART - what you are seeing is your stove performing efficiently. That is how the EPA approved stoves will perform.

The Quad will burn very clean almost from the start.

Initial woodsmoke will be amost grey until the fire gets hot enough to start burning it; then when you engage your secondary burn there will be either nothing but heat waves, or a little white steam.
The old stoves would put out grey to dark grey smoke depending on the wood; that is the smoke that easily produces significant creosote and it is NG.

The folks that have those old stoves can avoid these conditions by burning hotter, but sometimes they damp down and get that smoke.

I'm with the idea that black smoke will be tires or something pretty caustic which shouldn't be burned in the first place.

That sweet smell is common to many new stoves, it is just a hint of the wood burning.
And, finally, those CAT stoves produce almost nothing and unless you get up there and sniff it you can't smell it at all.

I can usually smell a hint of smoke when I come in from the cold, but soon after being inside get use to it and can't really smell it anymore. People who come over to visit usually notice the slight hint of smoke right away.
 
Here are my beliefs...

White smoke is cold smoke, the white is water that has condensed into steam. I'll get this on new fires and reloads. Anybody with constant white smoke is burning wet wood and/or a very cold stove.

Blue smoke is hot smoke plus unburnt fuel. I'll get this if I damper down a hot fire too quickly. Never very much of it and it generally rises much more quickly than white smoke since it is so much warmer. Many people get constant blue smoke if they have good wood, a good hot stove, but are dampered way way down for a long burn. The new EPA stoves make getting blue smoke tougher with their minimum draft settings.

Black smoke is petroleum.
 
Black smoke with that industrial smell is creasote burning from the chimney or flue. When I have a good hot firebox and complete combustion, it doesn't smell like wood. I notice the pleasant smell with a light blue smoke and a smell that will make you gag when its dark grey.
 
I hope the sweet smell never goes way. Its a great indicator that my stove is at proper temp. Have yet to smell the creosote smell. I have gotten in the habbit of burning a really hot fire for 20min after each reload. I just checked my chimney yesterday and other than the stove pipe going in the the chimney its clean. As for smoke color... I have been burning almost 24/7 since Nov. 20th and my neighbor was shocked when she seem me stacking wood last week. She said that she had no idea I was burning.
 
My old Royall boiler put out brown smoke when I would load it up with dry wood. Really stinky, brown smoke.

The new gasifier doesn't smoke at all after it gets started. Occasionally, you'll get a whif of kind of a sweet, hot wood smell. Even on a cold startup, the EKO smokes less than the old one did when it was burning "clean." Last spring I had a small pile of partially-burned chunks that I pulled out of the old boiler and tossed into the snow at various times during the winter when the wind shifted and started blowing at my neighbor's house. That's when I decided that we were overdue for an upgrade. Now I burn with impunity.
 
I usually ahve white/grey smoke the first half hour and then once the stove is up to a good temp its disappears!
 
dlpz said:
BrotherBart,

Thanks for the Pic! I downloaded and watched the video of the guy and girl in Canada building and burning a fire with no emissions.

It would be cool to see some pics of chimneys during start up, burning along and then restarting the fire from coals so newbs like me self have a base line for what (or what not) one should see coming out of the chimney. I know it depends on the stove and wood and etc., but without opening a can of worms, I think it would help. It would help me at least.

So I like to answer my own questions.

First year burning and am satisfied with what comes out of the stack, nothing. Cruising around 450-500 here's what's coming out of my stack:
 

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Looks like you have it figured out. Dry wood and good temps is is the best way to achieve this along with any type of secondary burn system.
Your pat on the back is in the mail. :) Way to go dlpz. You are making a positive for all wood burners to show people how clean they can really burn and not pollute.
 
You know there is something we sometimes overlook as well. That is a good chimney/draft. When sized properly the stack has much to do with how the stove burns.
I was out to Vermont today and saw many old farm chimneys smoking like crazy. You know that those folks do not have EPA stoves and are using about twice the wood as well.
I have an old non EPA stove in my shop and it also does not smoke after I light it off, that is because I installed an aftermarket CAT burner right at the outlet of the stove: it performs just like any other CAT stove.
I am burning more wood this year; because it is colder. But, I think less than I was with the VC stoves.
I can't say how happy I am that I moved to the Hearthstone from the VC's. I also think I would have been happy with Englander, PE, Quad or Morso: they are all great stoves.
This is a thing that new burners need to really digest; get a good stove and get a good chimney system: they go hand in hand.
And, BB that is one sweet set up you show in the pic! SW
 
I get the white smoke/steam when it gets around 0* during the first couple of hours of the burn. I am assuming it is vapor but am I creating creosote? :bug:
 
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