Smoke falling from chimney

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Campcook

Member
Nov 8, 2017
30
New Hampshire
I've just bought a 1700's farmhouse with a three fireplaces running off a central chimney. Two of the fireplaces have free-standing wood stoves and the third is blocked off and unusable. The stoves are OLD. One is an unidentifiable steel box in the kitchen (no fire brick, no baffling, nothing inside) that fits about 90 SF of wood and doesn't throw any heat. We used it once and won't use it again. The other stove is an All Nighter Box Moe that works pretty well and is our primary source of heat until we can get in something more efficient.

The issue I'm having is that smoke is always falling from the chimney into the back yard or the street. It really fogs up the place. We've also had a few occasions where the fire will be going well, stove up to temp, and then smoke will start pouring in through the front air control. To top it all off, the other day smoke was pouring in through the damper in the stove we DON'T USE. Must have rolled up one chimney and down the unused one right next to it.

Most of my wood is 20% tested on a freshly split face, but I admit that some of it is unseasoned. We moved in in the middle of winter and basically had to take what we could get for firewood. I try to toss the unseasoned pieces aside as I grab wood for the day. Both chimneys are lined and capped.

Any idea why my smoke keeps falling? I know the old timers say falling smoke means falling weather, which I've always found to be true but this is happening EVERY DAY.
 

ctyankee

Burning Hunk
Oct 25, 2019
184
connecticut
The flues are clogged by creosote? Huge fire risk!! Do not use anymore until inspected by a professional.
 
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ctyankee

Burning Hunk
Oct 25, 2019
184
connecticut
Does the 3rd fireplace that is blocked off have a thimble for stove pipe through it? Probably loaded with creosote behind the block off.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
30,158
central pa
I've just bought a 1700's farmhouse with a three fireplaces running off a central chimney. Two of the fireplaces have free-standing wood stoves and the third is blocked off and unusable. The stoves are OLD. One is an unidentifiable steel box in the kitchen (no fire brick, no baffling, nothing inside) that fits about 90 SF of wood and doesn't throw any heat. We used it once and won't use it again. The other stove is an All Nighter Box Moe that works pretty well and is our primary source of heat until we can get in something more efficient.

The issue I'm having is that smoke is always falling from the chimney into the back yard or the street. It really fogs up the place. We've also had a few occasions where the fire will be going well, stove up to temp, and then smoke will start pouring in through the front air control. To top it all off, the other day smoke was pouring in through the damper in the stove we DON'T USE. Must have rolled up one chimney and down the unused one right next to it.

Most of my wood is 20% tested on a freshly split face, but I admit that some of it is unseasoned. We moved in in the middle of winter and basically had to take what we could get for firewood. I try to toss the unseasoned pieces aside as I grab wood for the day. Both chimneys are lined and capped.

Any idea why my smoke keeps falling? I know the old timers say falling smoke means falling weather, which I've always found to be true but this is happening EVERY DAY.
What is the flue setup for these stoves?
 

ctyankee

Burning Hunk
Oct 25, 2019
184
connecticut
When I wrote "flues," I should have wrote "liners." I was in such a hurry I missed that part. But it doesn't matter. The liners must be clogged with creosote.
 
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Campcook

Member
Nov 8, 2017
30
New Hampshire
Does the 3rd fireplace that is blocked off have a thimble for stove pipe through it? Probably loaded with creosote behind the block off.
I thought of creosote too but we swept when we moved in and got A LOT of junk out of the pipe. We have a professional scheduled to inspect and do a thorough sweep as I'm sure we missed stuff.

There are no thimbles, the liners run right up the 250 year old fireplaces. The one that's blocked off isn't he problem, the smoke came out of the stove that is technically operational but that we've chosen not to use because its so inefficient.
 

Campcook

Member
Nov 8, 2017
30
New Hampshire
What is the flue setup for these stoves?
A central chimney with three separate flues. Two are lined with insulated liners and one is stuffed with insulation and maybe capped at the top--we'll find out the deal with that one for sure when the pros come to inspect the stoves.
 

ctyankee

Burning Hunk
Oct 25, 2019
184
connecticut
The one that's blocked off isn't he problem
My point was sort of an aside. Typically these were blocked off, and then a stove pipe was put a few feet up through hole, never to be cleaned, burning wet wood --- lots of creosote. This can affect the other flues as they all meet about halfway up in your attic. Two story or one story plus attic house?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
30,158
central pa
A central chimney with three separate flues. Two are lined with insulated liners and one is stuffed with insulation and maybe capped at the top--we'll find out the deal with that one for sure when the pros come to inspect the stoves.
Hmmm that eliminates my first thought
 

peakbagger

Minister of Fire
Jul 11, 2008
7,685
Northern NH
Hard to guess without more details. Liners have to be sized the wood fired appliance, too big and the velocity is too low. Creosote will sometimes help in that it drops the effective diameter raising the velocity but this effect only lasts a short time until the pipe is choked off. There are also site conditions that can cause issues but usually on cold day smoke should be going straight up.
 

stoveliker

Minister of Fire
Nov 17, 2019
6,216
Long Island NY
Is the chimney protruding at least 3 ft above the ridgeline (or 3 ft above anything within a 10 ft radius)?

Any trees nearby? Correlation with wind direction?
 

richmhv

Member
Oct 30, 2014
40
Shokan NY
Are you on a slope or near the base of a hill? You may have sinking air around your house. I am located on the lower southern slopes of a mountain so north breezes come at my house also moving downward. That tends to blow smoke downward so that I can often smell my smoke in the yard. A taller chimney might help.
 

Campcook

Member
Nov 8, 2017
30
New Hampshire
Is the chimney protruding at least 3 ft above the ridgeline (or 3 ft above anything within a 10 ft radius)?

Any trees nearby? Correlation with wind direction?
At a glance, it looks like the brick chimney is about 3 feet above the roof line with the liner cap sticking out another 12 inches or so. We have a pretty big yard and the wind really whips through, but the smoke falls even when there's no wind.
 

Campcook

Member
Nov 8, 2017
30
New Hampshire
Are you on a slope or near the base of a hill? You may have sinking air around your house. I am located on the lower southern slopes of a mountain so north breezes come at my house also moving downward. That tends to blow smoke downward so that I can often smell my smoke in the yard. A taller chimney might help.
This is an interesting thought. There are several mountains near by but I wouldn't say we're in a valley.
 

weatherguy

Minister of Fire
Feb 20, 2009
5,906
Central Mass
I smell smoke in my yard from time to time and my liner is as clean as a whistle. My wood is well seasoned and burns with no smoke so I'm burning clean. I think it has something to do with location and winds.
 

peakbagger

Minister of Fire
Jul 11, 2008
7,685
Northern NH
If you are familiar with Chinese Sky Lanterns they are kind of handy to get an idea on the local wind patterns. Definitely only to be used with snow on the ground and launch from a clearing. I have launched them in a few spots and they will start traveling upwards in one direction then once they get up a bit the higher level winds will grab onto it. I also have also launched them in dead calm on the ground and then start to get blown around not that far off the ground. Fun to play with on cold winter night.

The odd part is that usually draft issues go away in cold weather, if you get this all the time is sounds like issues with the flue.
 

john26

Minister of Fire
Oct 27, 2008
781
Wildwood MO
One of my inserts will do that on start up and sometimes on reload. Clean flue 6" lined and insulated about 4' above roof t4'. I believe its due to roof design and winds. The chimney is on the corner of the house, I have felt winds pushing pushing down ward on the back side of the ridge.
 

fbelec

Minister of Fire
Nov 23, 2005
3,422
Massachusetts
how are you testing your wood and what temp is the wood when tested? not the air temp. normally if your smoke is going down instead of up it means the smoke and fire is to cool if the wind is not taking it. if it does it on a calm day or night it's wet wood