Stove pipe backwards?

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aarolar

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Is it true that your supposed to install single wall stove pipe with the joints opposite of what is common in normal duct installation? I am have issues with creasote running back out of my joints burning good seasoned wood. My fathers stove was installed in the same manner and he regularly burns green wood and has never seen this issue?
 
Stove side goes inside the chimney side...hope that makes sense?

Now, where is the creosote coming from is the next question?

Let's assume this is a normal amount of creosote (i.e. very little), so that everything is burning OK with the stove. Creosote forms when the smoke cools before leaving the chimney, as the moisture and volatile unburned oils condenses out it takes solid particles with it and deposits them on the side of the chimney. This can flow like tar when warm.

On an outside chimney like mine, what there is should flow down the chimney, past the thimble, and to the clean out. The only thing I get in my single wall stove pipe between the stove and thimble is a build of ash that flies up there when I'm cleaning the stove.

I'm not sure how folks with chimney liners or pipes that go straight up and through a chimney in the roof deal with it.
 
Not just single wall, all stove pipe should be installed with the "male" end closest to the stove.
Moisture condensation and/or heat can "liquify" soot and creosote in the pipe, casing it to flow down and out the joints if the pipe is installed "male" end away from the stove.
Do you have a cap on your chimney to keep rain out?
Does it have a relativity long outside run (such as up and outside wall)? A "cold" pipe will cause heavier creosote build-up and more moisture condensation.
 
Is it true that your supposed to install single wall stove pipe with the joints opposite of what is common in normal duct installation? I am have issues with creasote running back out of my joints burning good seasoned wood. My fathers stove was installed in the same manner and he regularly burns green wood and has never seen this issue?

I'm not sure what you mean by "backwards" but the rule is the narrow ends point down, "into" the larger joint ends of each piece below it. With a proper chimney draft there's (slight) negative pressure in the pipe, so you're not worried about smoke "leaking out" up through the seams. You DO worry about creosote, and this makes sure that as it drips down the chimney, it stays inside the pipe. Creosote outside the stove pipe is very bad news.

Narrow end down.
 
The outside run is less than 3' and I do have a rain cap. My pipe is together narrow end toward the chimney so by stove standards it is backwards. Here are a few images of what I am dealing with I intend on swapping it around this afternoon when I get home hopefully its a pretty quick fix because it supposed to be chilly tonight.

2012-11-06_04-07-49_305.jpg
 
Yeah, it's backwards. Don't worry, I've done that too thinking that the smoke would go up, and out the joint.
Flip it around if you can, or it's a good time to put new pipe in.

Having smelly creosote does not make for a happy wife.
 
I've done that as well and changed it as soon as I found out different. Yes the joints are backwards. You want the creosote to stay inside, because if you ever have a flue fire, it is better to be contained inside the pipe. Imagine how bad having the fire outside the pipe would be. It would keep running down and feeding itself until the chimney was empty. That seems to be alot of creosote to me.
 
Over the years there has been a reversal of which way is correct. Gas aplliances are still installed the direction you did and the old pot bellys and such were always installed with the joints same way. Then when the fabricated air tight stoves came to be and with them the liquid creosote problems stove outlets were changed so as the male end of the pipe went down so the liquids would leak all the way back into the stoves. When you think about it which way they are installed makes almost zero differance as to the leaking of gasses or smoke since the differantial pressure is what keeps the joint from leaking in the first place not any kind of sealing in the joints. All in all I am glad that mess is now loacted outside at our place;)
 
That must be why my father doesn't have the issues I do he has a newer stove that is far from airtight.
 
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Yes, crimped end goes down. If you have an old stove the joint at the stove used to be made such that that one hunk of pipe could not be inserted that way. Why? who knows, it was stupid. If you need to make an adapter such as one crimped on both ends anyplace selling stove pipe can do it for you.

My ex-neigbor had that problem, asked me what to do, I told him his pipe was upside down. His answer? "BS". Far as I know the pipe was still upside down and totally black on the outside when he moved out.

Harry K
 
One other thing...Put 3 screws in each joint. If you would ever have a flue fire, the forces created by it could push them apart.
 
My friend did that at his cabin. What a stink that creosote makes burning down from the outside of the joints. It took weeks to get that smell out of the cabin. Male end always down toward stove.
 
Harry's right. Over the years I've had real super smart folks say the same thing. Then I had to remind them about how the draft works. And remind them of the store and the running stove you could watch the smoke rise up in the open pipe and the guy stuck his hand in it..."Oh yeah!" they'd say.
 
Except that "common sense" leads to putting it in wrong :) "gotta have crimped end up or the smoke will leak out into the room".


Harry K

Guilty. I thought of it as I would a car exhaust (which is the exact opposite principle). But mine is only a short section leading to a masonry chimney, so I'll leave it as is till next time I clean it.
 
Ok, when I put my stove in last year, I naturally assumed the crimped ends pointed up because if it were opposite, the smoke would come out between the crimps. I haven't had any smoke issues so far. So did I do it right, or did I do it wrong? R2
 

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