My total length of chimney is only 12’....Could this be too short?

[JPapiPE]

I thought i had read some place in the stove manual that a chimney including all pipe should be at least 14 feet. My chimney is a straight shot from the stove out through the roof with no bends or elbows. Do you expect I'll have draft problems. I do have a 3" fresh air intake connected from the stove to the outside. At this 12' length my chimney is 3 feet over the ridge as i have a very low pitched roof.
Thanks for any feedback

 

[begreen]

Is that 12 feet from the top of the stove to the flue cap? Or is that from the floor to the flue cap?

 

[Todd]

Hard to say for sure til you try it out. Since it's a straight shot you may be ok.

 

[begreen]

Yes, I'm thinking it will be fine. That's why I recommended going straight up with double wall interior in the first place. If this is 12' of actual flue pipe then it is very close to the required 15" off of the floor spec.

 

[Highbeam]

My stove had a minimum chimney length listed in the manual. I was able to meet the minimum with a very similar straight shot. It drafts well. Chimney length is chimney length which is not typically measured from the floor since your chimney doesn't go to the floor. Hopefully the method of measurement is also included in your manual.

12' is pretty decent with your cold Maine temps.

 

[Noah]

Mine is only 8 feet of actual chimney not including 5.5 feet of connector pipe, I'm hoping that's going to be enough. If not it's easy to add sections to the top.

 

[begreen]

It can be confusing, but chimney height is sometimes measured from the floor in manuals. Such is the number that Joe is referring to.

 

[JPapiPE]

My 12' measurement is from the top of the stove, which sits 27" off the hearth pad

 

[Noah]

From my manuel, not very specific.

Chimneys shorter than 14 feet (4.27 m) may not provide adequate
draft. Inadequate draft can result in smoke spillage when loading
the stove, or when the door is open. Poor draft can also cause back
puffing (ignition of gas build-up inside the firebox) and sluggish
performance. The minimum height does not, in itself, guarantee
proper chimney performance.

By chimney are they referring to the actual chimney or are they including the connector pipe in this measurement as well?

 

[begreen]

Try it out on a cooler day than today Joe. I think it will be ok.

 

[mayhem]

Others know better than I, but I'm under the impression that the really important factor is that the top of your chimney extend beyond the highest airspace in your home, which means its sticking into a region of slightly lower pressure than you can have inside your house. Check your sate building code to be sure you don't have some sort of violation too, there may be a good answer rihgt there.

But the best way to know for sure is to run that sucker. Next moderately chilly night fire it up and see how she does...if its poor consider tacking on a few feet to the outside. Sounds like this is a new install anyway so I'm assuming you have yet to do your break in fires, so now is a good time to do it when you can run the stove for awhile to cure the paint and the seals with your house windows open.

 

[begreen]

From my manuel, not very specific.

Chimneys shorter than 14 feet (4.27 m) may not provide adequate
draft. Inadequate draft can result in smoke spillage when loading
the stove, or when the door is open. Poor draft can also cause back
puffing (ignition of gas build-up inside the firebox) and sluggish
performance. The minimum height does not, in itself, guarantee
proper chimney performance.

By chimney are they referring to the actual chimney or are they including the connector pipe in this measurement as well?

In this case, for your stove, they mean the entire flue length from stove to cap. Unfortunately instructions are not consistent from company to company.

 

[JPapiPE]

I think the constant supply of cold air coming throught the 3" flex metal pipe from outside the house and attached to the stove directly may make this work. Or I'll just add more pipe.
Thanks to all that posted Joe

 

[savageactor7]

Joe a straight shot is perfect...tonite when it cools down crumble up some newspapers and throw them in there with the door closed...that'll give you an good idea on how your drafting. Oh yeah go outside and check it out too.

Now if your chimney is below peak on the lee side...sometimes (BUT not all the time) you could have draft issues. It's a terrain/tree deal and there's no rule of thumb...at least around here.

 

[offroadaudio]

I think the constant supply of cold air coming throught the 3" flex metal pipe from outside the house and attached to the stove directly may make this work. Or I'll just add more pipe.
Thanks to all that posted Joe

I'm wondering if lowering the intake of the flex would in effect increase draft or "add chimney height"?
In other words - if the intake air is coming from just a few inches above ground level, it is even denser than the air at the current chimney height. Would the effect be the same?

 

[Highbeam]

Ahhh, you notcied that too Joe? My outside air connection constantly drafted air as well making for a "supercharged" stove. In fact, I am fairly certain that the stove is running air through it all summer too even with no fire burning. Good crawlspace ventilation I suppose.

 

[Carl]

From the quote of the posted manual the big word is....MAY......this doesn't mean it will not work. They are protecting themselves if you do have problems. With a straight run I think it won't work fine.

Probably the ones that have had problems are those with short chimneys and many elbows. Just my thought on the subject.

 

[JPapiPE]

I think "Off Road Audio" if i remember my lessons from my scuba diving class that air pressure at the earths surface is 14.7#/cubic inch and does not change until one is immersed into water of a depth of 1 atmosphere or 33 feet under water. Meaning in simple terms that a normal person consumes 1 cubic foot of air / minute on the earths surface. Todays scuba tanks usually carry 80 cubic feet of air, meaning that if one were using a scuba tank on the surface of the earth he would have 80 minutes of air. He would also have 80 minutes of air underwater unless he penetrated to below 33 feet. Then the air consumption becomes a logarithm of 1/2 the depth at a specified atm. Simply put ..if a diver stays below 33 feet but does not exceed 66 feet his air will last him 40 minutes. It's an over simplication and i have forgotten so much ...but i think I'm right. Can some of divers chime in and help me with a more simple explanation
Thanks Joe

 

[offroadaudio]

I think "Off Road Audio" if i remember my lessons from my scuba diving class that air pressure at the earths surface is 14.7#/cubic inch and does not change until one is immersed into water of a depth of 1 atmosphere or 33 feet under water. Meaning in simple terms that a normal person consumes 1 cubic foot of air / minute on the earths surface. Todays scuba tanks usually carry 80 cubic feet of air, meaning that if one were using a scuba tank on the surface of the earth he would have 80 minutes of air. He would also have 80 minutes of air underwater unless he penetrated to below 33 feet. Then the air consumption becomes a logarithm of 1/2 the depth at a specified atm. Simply put ..if a diver stays below 33 feet but does not exceed 66 feet his air will last him 40 minutes. It's an over simplication and i have forgotten so much ...but i think I'm right. Can some of divers chime in and help me with a more simple explanation
Thanks Joe

I would know that if I had taken scuba lessons with my BIL.
Thanks for the info!

'Frank

 

[stoveguy2esw]

Joe a straight shot is perfect...tonite when it cools down crumble up some newspapers and throw them in there with the door closed...that'll give you an good idea on how your drafting. Oh yeah go outside and check it out too.

Now if your chimney is below peak on the lee side...sometimes (BUT not all the time) you could have draft issues. It's a terrain/tree deal and there's no rule of thumb...at least around here.

he doesnt have the flue installed yet , we're working on it. personally i htink he will be ok the 13 drafts easily comapred with a lot of EPA units. 12 from the stovetop is durn near 15 from the floor anyway.

 

[savageactor7]

Joe a straight shot is perfect...tonite when it cools down crumble up some newspapers and throw them in there with the door closed...that'll give you an good idea on how your drafting. Oh yeah go outside and check it out too.

Now if your chimney is below peak on the lee side...sometimes (BUT not all the time) you could have draft issues. It's a terrain/tree deal and there's no rule of thumb...at least around here.

he doesnt have the flue installed yet , we're working on it. personally i htink he will be ok the 13 drafts easily comapred with a lot of EPA units. 12 from the stovetop is durn near 15 from the floor anyway.

Whoops ...apparently I have a reading comprehension problem...my bad.

 

[JPapiPE]

I did burn the stove last night like you suggested and all the smoke detectors went off... I think i will wait until i get my chimney hooked up before trying this experiment again.
LOL Joe