Is There a Mathematical Formula for Stove Pipe Length?

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Gypo Logger

Timber Baron
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Ok, I'm in my 24x10 shack and I'm getting smoked out for some reason. My eyes are burning and I feel like a smoked salmon. It's only 2F out and the barometric pressure is 100.9 kpa. I'm burning dry swamp spruce and it only smokes when I try to dampen it down. The stove is a small Drolet airtight and the 6" pipe is about 8'. Shall I just wait for colder weather for a better draft or am I experiencing a thermal inversion or is my pipe to short.
Because its so warm out I sleep with at least 2 windows open along with all the accociated drafts as I don't want to end it all as of yet.
Thanks for any help.
John
 
8' total? Chimney and all? If it is, then you are WAY too short. I believe that stove calls for a minimum 15' chimney height
 
That's good to know thx. From the stove to the ceiling is appox 5' the roof, which I didn't consider is about a foot thick and there's about 3 ft sticking above the roof with no rain cap. I also rattled a 4' stick down the pipe in case it was creosote issue and took a hammer to the pipe inside the shack for the same reason.
I'll go to the dump tomorrow to see if I can find another 3' section.
You very well could have saved my life in the event I got drunk and never woke up.
Thx again
John
8' total? Chimney and all? If it is, then you are WAY too short. I believe that stove calls for a minimum 15' chimney height
 
Is this a new installation for you, or just a new experience? If just a new experience, I would guess a rather severe pipe restriction. At the temp you are at, a hot fire should be drawing hard.

Our ancient brick jobber is about that high from the point the inside pipe attaches to it, always draws well, even when it is warm out. I don't run an exhaust damper at all though, unrestricted, a single 90 pipe elbow bend going into the chimney. When it is cold (for here) that bad boy can suck some air.
 
Is this a new installation for you, or just a new experience? If just a new experience, I would guess a rather severe pipe restriction. At the temp you are at, a hot fire should be drawing hard.

Our ancient brick jobber is about that high from the point the inside pipe attaches to it, always draws well, even when it is warm out. I don't run an exhaust damper at all though, unrestricted, a single 90 pipe elbow bend going into the chimney. When it is cold (for here) that bad boy can suck some air.
Thanks for your reply zogger, it's really a new old installation. I got it for 50 bucks and installed it 2 months ago after the custom made stove I replaced it for had holes in the jacket from getting red hot the last 3 years.
There's a pipe damper on this one I installed, hence the smoking if I close it although it never smoked before.
I just replaced the door gasket so the wood would last into the cold nights as I live off the grid and it's the only heat source other than a propane lamp.
I sure miss the side loader I had back east and the blaze king I had before I moved here.
Thx
John
 
as long as you are 2 feet above the highest obstruction of the roof line you should be good to go! at 3 feet your even better to draw a draft through the stove pipe. only other thing you might try would be to increase the size of the flue pipe to a 7" or an 8" for better outlet relief! kinda like a snow/mud clogged tail pipe and the engine wont run.....
 
as long as you are 2 feet above the highest obstruction of the roof line you should be good to go! at 3 feet your even better to draw a draft through the stove pipe. only other thing you might try would be to increase the size of the flue pipe to a 7" or an 8" for better outlet relief! kinda like a snow/mud clogged tail pipe and the engine wont run.....

^^^^^that is all wrong^^^ short answer is, don't dampen down the damper. If it can't go through the night you need a bigger stove.
 
as long as you are 2 feet above the highest obstruction of the roof line you should be good to go! at 3 feet your even better to draw a draft through the stove pipe. only other thing you might try would be to increase the size of the flue pipe to a 7" or an 8" for better outlet relief! kinda like a snow/mud clogged tail pipe and the engine wont run.....
That'd be a mistake. Keep the 6" the whole way up. Going bigger slows the velocity and therefore the temp, which lowers draft. Oh and the rule of thumb is 2' higher than anything else within 10' horizontally of the chimney
 
That'd be a mistake. Keep the 6" the whole way up. Going bigger slows the velocity and therefore the temp, which lowers draft. Oh and the rule of thumb is 2' higher than anything else within 10' horizontally of the chimney

The temp drop will cause it to Creosote like mad, if you just slide 8" over the existing 6"
 
I did slide an 8" insulated pipe over the roof pipe to keep creosote down. When it's minus 20 or more it draws well and I can starve it for air. But at warm temps it too hot wide open and smokes if I dampen down too much. I've got no shortage of free wood, so maybe when it's warm like this Ill let it rip with the front door ajar. But I always have to rekindle in the morning. This shack isn't well insulated but when the snow comes I pile it deep around the shack which helps a lot to keep the cold out.
 
Sorry, meant non insulated pipe. Insulated wont have near the problems.
 
slow your fire down, before you shut it down.
close the chimney flue part way, and shut down your primary and secondary air......wait 10 minutes, then see if you can close the chimney flue all the way.
also, the holes on the flue can get sealed with creosote......and that will prevent you from closing it all the way.
 
I believe that stove calls for a minimum 15' chimney height
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If you are reducing the flue draft with the flue pipe damper, then what good would a longer pipe and more draft do? Don't you already have more draft than you need?
 
If you are reducing the flue draft with the flue pipe damper, then what good would a longer pipe and more draft do? Don't you already have more draft than you need?
Yes and no. When I got up this morning the temp inside was 33F and outside temp was -5F and the fire was out with ashes warm to the touch.
Maybe I'll sleep with less bedding so the cold wakes me up to put more wood on.
Ill take some pics.
 
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