More smoke when it's cold?

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Enplater

Burning Hunk
Jun 6, 2017
244
NH
So I just looked at my stack before bed and noticed that its smoking like a train. It's +1 deg f right now and I just loaded the stove with good dry hard wood and got it nice and hot before turning it down to go to sleep. I have an Englander 30 so I'm not used to seeing any smoke, I'm thinking it's not smoke but condensation or something since the smoke is very white in color and the air temp is so cold.
 

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You are exactly right, it's condensation. When it's super cold out the smoke looses it's velocity and kind of floats around lazily (lamiliar).
 
What I thought, thanks.
 
Yep, steam
 
If there's a little breeze, you'll see that steam is 'lighter' and is more easily swirled around by the breeze. Smoke has a 'heavier' look to it. And of course there's the color difference that you noted.
 
I’m getting this to for the past few days has had me worried it’s been very cold here -20 to -29 Celsius and there seems to be a lot of smoke or steam that I haven’t seen before it starts about half a foot off the chimney I can see the heat waves coming out than the steam starts kind of has me worried hoping it’s just steam and not smoke ?


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it starts about half a foot off the chimney I can see the heat waves coming out than the steam starts kind of has me worried hoping it’s just steam and not smoke ?
Yep, steam..smoke would be visible leaving the chimney. Water vapor has to cool down before it condenses, that's why it's not appearing until it's a foot from the chimney. If the temp at the top of the flue is cooler, steam may appear attached to the chimney. Then it may disappear within a few feet of the chimney, if the air is very dry. If it humid, like it often is here, the steam can carry 30' or more from the chimney.
 
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Mines doing it to, more so with the bitter weather.
 
If you have visible waves heat at the mouth of the stack and then a white plume inches to feet away - EPA says you can read the opacity of the smoke component of your exhaust plume at the mouth of the stack and ignore the steam that forms later / further out.

What the OP is describing is a stove that is running pretty clean - zero opacity between the the stack mouth and the detached steam plume.

This does suggest the exhaust gas temp at the stack exit is > 212 dF and the steam in the exhaust plume is condensing as water vapor away from the stack mouth.

Given the weather in the lower 48 right now I would take it and like it.

The actual pic in post one looks like steam to me, but attached to the top of the stack. It isn't "legal" that I know of to read the pollution in an exhaust plume from a photograph, but I would not be super worried if I saw that. Long term having the steam plume attached to the top of the stack means the steam in the exhaust plume is condensing down inside the chimney somewhere. There is probably some creosote collecting up in the top few feet of the stack pictured in post one.

Again, given the current weather in the lower 48 right now I wouldn't lose any sleep over it tonight. If you can brush your chimney from the bottom up in a couple weeks when the weather breaks it might be a good idea. Also keep an eye out for stove performance to be falling off or drifting down. If the draft gets to acting "sluggish" or "weak" it is probably time to brush the pipe.
 
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Good information, thanks again
 
I have a large 70 MW Biomass fired power plant in a nearby town. Its the largest in New England. On cold sunny days with no wind the stack plume is quite impressive and can be seen for miles. Coal plants with wet scrubbers also have some pretty impressive plumes on cold days.

I work on large plants on occasion and when I am driving around in new territory on cold days I keep an eye out for stack plumes and try to guess what plant it is.