Too Much Draft?

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eclecticcottage

Minister of Fire
Dec 7, 2011
1,803
WNY
We just had the stove drafting like mad-it was sucking embers right up the flue and tossing them out the cap. We adjusted things and it pretty much stopped. Never saw that before....well, ok, once when it was REALLY windy out, which it is not at the moment. Are the only solutions a taller stack or in flue damper?
 
A taller stack will give you "More Draft".

How tall is your current flue? Single wall? Double wall?

A key damper can be a good idea. I installed one. Although I have only used it on "runaway" situations (overfire).
 
Sounds like a small chimney fire to me.
 
I thought it might have been also, but I could see it sucking little embers off the ecobricks...the bricks turn "fluffy" when they burn down and that was what it was sucking up. No unusual noise or glowing anywhere, just little sparks popping out the cap (not a profuse amount, just enough that if you stood there and watched it, you wouldn't think whomever told you they saw it was nuts and walk away before seeing them). I will concede that it might well have been though....
 
If they puff stuff up in the pipe then lighting the stuff they stick in the pipe lighting off every once in a while is a non event.
 
Yeah, it wasn't like a fireworks show or anything like that. We do plan on getting a steel roof eventually, but in the mean time it's a bit disconcerting when it does it! I don't think any even made it to the roof while still glowing, I know none made it to the ground because I was watching so I could go look at one if I could find it when it landed to make sure it seemed like the fluffy ash the bricks can create. No dice, they went dark before making it past the roof line.

We have a single story, but the stack exits right by the peak, I'm guessing it's @ 18' from the stove to the cap. Double wall.
 
The flue length is just about perfect. When was the chimney last checked/cleaned for creosote?
 
eclecticcottage said:
We just had the stove drafting like mad-it was sucking embers right up the flue and tossing them out the cap. We adjusted things and it pretty much stopped. Never saw that before....well, ok, once when it was REALLY windy out, which it is not at the moment. Are the only solutions a taller stack or in flue damper?


Check out this article on the "Florida Bungalow Syndrome".
http://www.gulland.ca/florida_bungalow_syndrome.htm

It has a table that illustrates the relationship between pressure differential (draft), stack height, and temperature differential (average stack gas temperature delta to outside air). Consider your stack height, obtian the outside air temperature the night you had the issue, swag your flue temp, and you can estimate the amount draft you experienced that caused embers to get sucked up the flue.

The article also discusses four alternatives to controlling the firing rate in your stove which is the key parameter in operating stoves, one of which is air inlet modification which folks periodically re-'discover' and post about on this forum. The alternatives discussed in the article give you options to modify your setup to increase the amount of control you have over draft. It also will sensitize you to the factors that modulate draft - so you can avoid the "big suck" in the future.
 
If BB is correct, and I suspect he is, then this is not a draft issue.
 
BeGreen said:
If BB is correct, and I suspect he is, then this is not a draft issue.

Actually, when you look at the table in article, and consider the effect that a chimney fire has on draft due to an elevated flue temp to outside air temp differential, then then excessive draft is exactly his problem.
 
In the case of a chimney fire, excessive draft is a symptom, right? The problem is a dirty flue. You don't solve the problem by any of Gulland's 4 prescribed solutions. You solve it with a chimney brush and burning drier wood.
 
BeGreen said:
In the case of a chimney fire, excessive draft is a symptom, right? The problem is a dirty flue. You don't solve the problem by any of Gulland's 4 prescribed solutions. You solve it with a chimney brush and burning drier wood.

Well, no - his problem was embers being sucked up the flue. If he had creosote burning in his flue, he appears to have been content to let it burn, his only concern appears to have been the embers leaving the firebox.

Several of Gulland's solutions, such as the damper assembly arrangeable to obstruct the flue, would have solved that particular problem. A chimey brush, in contrast, would have been of very little assistance - particularly given the active fire(s).
 
I think she indicated a temporary condition. "We just had the stove drafting like mad-it was sucking embers right up the flue and tossing them out the cap."

You could be right, but so far I haven't seen evidence of excessive draft on an 18' chimney.
 
Biff_CT2 said:
BeGreen said:
In the case of a chimney fire, excessive draft is a symptom, right? The problem is a dirty flue. You don't solve the problem by any of Gulland's 4 prescribed solutions. You solve it with a chimney brush and burning drier wood.

Well, no - his problem was embers being sucked up the flue CORRECT(not so much sucked as drafted as all stoves do). If he had creosote burning in his flue, he appears to have been content to let it burn (HIGHLY DOUBT ANYONE IS CONTENT OR HAS INTENT TO HAVE A CHIMNEY FIRE , AND AGAIN THE OP OBVIOUSLY IS NOT CONTENT AS THEY POSTED A QUESTION OF CONCERN ABOUT IT), his only concern appears to have been the embers leaving the firebox. (EMBERS AT TIMES AND UNDER SOME CIRCUMSTANCES CAN DRAFT UP THE STACK, HENCE THE USE OF A SCREEN ON THE CAP, WHICH IS MANDATED IN SOME STATES & AREAS).

Several of Gulland's solutions, such as the damper assembly arrangeable to obstruct the flue, ( DAMPERS DO NOT COMPLETELY CLOSE, SO EMBERS CAN STILL GET PAST THEM AND GO UP, DRAFT REMEMBER? IF YOU COULD STOP THE DRAFT ENTIRELY, GOOD LUCK WITH THAT SMOLDERING MESS AND I AM SURE THE CREO BUILD UP UP TOP WOULD TRIPLE).would have solved that particular problem. A chimey brush, in contrast, would have been of very little assistance - particularly given the active fire(s).
CHIMNEY BRUSHES CLEAN THE CREOSOTE HENCE, NO CREO, NO STACK FIRE, PRETTY SIMPLE. AND IN CASE YOU MISINTERPRETED, CHIMNEY BRUSHES ARE USED ON COLD STACKS.

There is no one fix for every similar problem. Read all the books you want, and watch all the videos to inform yourself. But nothing is gospel.
A stack kept clean, by both sweeping, good burning practices, and good dry wood, will not be catching ablaze if an ember makes it's way up there.
Todays lesson is concluded. Enjoy the warmth.
 
Hogwildz said:
Biff_CT2 said:
BeGreen said:
In the case of a chimney fire, excessive draft is a symptom, right? The problem is a dirty flue. You don't solve the problem by any of Gulland's 4 prescribed solutions. You solve it with a chimney brush and burning drier wood.

Well, no - his problem was embers being sucked up the flue CORRECT(not so much sucked as drafted as all stoves do). If he had creosote burning in his flue, he appears to have been content to let it burn (HIGHLY DOUBT ANYONE IS CONTENT OR HAS INTENT TO HAVE A CHIMNEY FIRE , AND AGAIN THE OP OBVIOUSLY IS NOT CONTENT AS THEY POSTED A QUESTION OF CONCERN ABOUT IT), his only concern appears to have been the embers leaving the firebox. (EMBERS AT TIMES AND UNDER SOME CIRCUMSTANCES CAN DRAFT UP THE STACK, HENCE THE USE OF A SCREEN ON THE CAP, WHICH IS MANDATED IN SOME STATES & AREAS).

Several of Gulland's solutions, such as the damper assembly arrangeable to obstruct the flue, ( DAMPERS DO NOT COMPLETELY CLOSE, SO EMBERS CAN STILL GET PAST THEM AND GO UP, DRAFT REMEMBER? IF YOU COULD STOP THE DRAFT ENTIRELY, GOOD LUCK WITH THAT SMOLDERING MESS AND I AM SURE THE CREO BUILD UP UP TOP WOULD TRIPLE).would have solved that particular problem. A chimey brush, in contrast, would have been of very little assistance - particularly given the active fire(s).
CHIMNEY BRUSHES CLEAN THE CREOSOTE HENCE, NO CREO, NO STACK FIRE, PRETTY SIMPLE. AND IN CASE YOU MISINTERPRETED, CHIMNEY BRUSHES ARE USED ON COLD STACKS.

There is no one fix for every similar problem. Read all the books you want, and watch all the videos to inform yourself. But nothing is gospel.
A stack kept clean, by both sweeping, good burning practices, and good dry wood, will not be catching ablaze if an ember makes it's way up there.
Todays lesson is concluded. Enjoy the warmth.

"Chimney brushes are used on cold chimneys" LOL (though I appreciate you clearing that up).

My point is a bit different.

If you understand draft as influenced by a group of factors - some of which you control and some of which you do not, then you're on the path to being to being able to operate you're stove well. The article I linked to explains some of the factors, and relates the factors to how a particular set up functions.

It is also a great starting point for chimney setup application for a mobile device.

One of the biggest problems with wood burning is having to rely on an expert's intuition and/or experience (real or imaginary) when selecting a stove setup initially. In my experience, a disturbing;y large proportion of these folks are full of crap or motivated by a quick payday. I'd love to see these folks (stove shop salesman/sweep 'experts') get replaced by a software application that a user can easily use to determine how well a given chimney/liner/stove combination works with their specific chimney and expected range of atmospheric and firing conditions.

A great place to start would be putting the table from the article and some what-if functionality into a cell phone app. Then you wouldn't have to rely on some bullshit artist behind a stove shop counter telling you that the manual is wrong and that it's fine to install an insert in a pre-fab fireplace (subject of another thread). Might actually save a life or two in the process...
 
BeGreen said:
I think she indicated a temporary condition. "We just had the stove drafting like mad-it was sucking embers right up the flue and tossing them out the cap."

You could be right, but so far I haven't seen evidence of excessive draft on an 18' chimney.
+ 1 there is always a first but I dont think its gonna happen in 18 feet.
 
Biff_CT2 said:
A great place to start would be putting the table from the article and some what-if functionality into a cell phone app. Then you wouldn't have to rely on some bullshit artist behind a stove shop counter telling you that the manual is wrong and that it's fine to install an insert in a pre-fab fireplace (subject of another thread). Might actually save a life or two in the process...

Here ya go. Bookmark this one for your smartphone browser.

http://fullmetalbullshiet.ytmnd.com/
 
oldspark said:
BeGreen said:
I think she indicated a temporary condition. "We just had the stove drafting like mad-it was sucking embers right up the flue and tossing them out the cap."

You could be right, but so far I haven't seen evidence of excessive draft on an 18' chimney.
+ 1 there is always a first but I dont think its gonna happen in 18 feet.

Intuitively, I think you're correct.

My preference, however, is to run the numbers and find out if there is a set of conditions where it happens - and then run my stove under other conditions.

Takes the guesswork out of running a stove, and makes the operation of appliance as safe as possible. Data doesn't lie, stove salesmen - they're another story.
 
BeGreen said:
Biff_CT2 said:
A great place to start would be putting the table from the article and some what-if functionality into a cell phone app. Then you wouldn't have to rely on some bullshit artist behind a stove shop counter telling you that the manual is wrong and that it's fine to install an insert in a pre-fab fireplace (subject of another thread). Might actually save a life or two in the process...

Here ya go. Bookmark this one for your smartphone browser.

http://fullmetalbullshiet.ytmnd.com/


Have you considered using that for your avatar?
 
Biff_CT2 said:
Hogwildz said:
Biff_CT2 said:
BeGreen said:
In the case of a chimney fire, excessive draft is a symptom, right? The problem is a dirty flue. You don't solve the problem by any of Gulland's 4 prescribed solutions. You solve it with a chimney brush and burning drier wood.

Well, no - his problem was embers being sucked up the flue CORRECT(not so much sucked as drafted as all stoves do). If he had creosote burning in his flue, he appears to have been content to let it burn (HIGHLY DOUBT ANYONE IS CONTENT OR HAS INTENT TO HAVE A CHIMNEY FIRE , AND AGAIN THE OP OBVIOUSLY IS NOT CONTENT AS THEY POSTED A QUESTION OF CONCERN ABOUT IT), his only concern appears to have been the embers leaving the firebox. (EMBERS AT TIMES AND UNDER SOME CIRCUMSTANCES CAN DRAFT UP THE STACK, HENCE THE USE OF A SCREEN ON THE CAP, WHICH IS MANDATED IN SOME STATES & AREAS).

Several of Gulland's solutions, such as the damper assembly arrangeable to obstruct the flue, ( DAMPERS DO NOT COMPLETELY CLOSE, SO EMBERS CAN STILL GET PAST THEM AND GO UP, DRAFT REMEMBER? IF YOU COULD STOP THE DRAFT ENTIRELY, GOOD LUCK WITH THAT SMOLDERING MESS AND I AM SURE THE CREO BUILD UP UP TOP WOULD TRIPLE).would have solved that particular problem. A chimey brush, in contrast, would have been of very little assistance - particularly given the active fire(s).
CHIMNEY BRUSHES CLEAN THE CREOSOTE HENCE, NO CREO, NO STACK FIRE, PRETTY SIMPLE. AND IN CASE YOU MISINTERPRETED, CHIMNEY BRUSHES ARE USED ON COLD STACKS.

There is no one fix for every similar problem. Read all the books you want, and watch all the videos to inform yourself. But nothing is gospel.
A stack kept clean, by both sweeping, good burning practices, and good dry wood, will not be catching ablaze if an ember makes it's way up there.
Todays lesson is concluded. Enjoy the warmth.

"Chimney brushes are used on cold chimneys" LOL (though I appreciate you clearing that up).

My point is a bit different.


If you understand draft as influenced by a group of factors - some of which you control and some of which you do not, then you're on the path to being to being able to operate you're stove well. The article I linked to explains some of the factors, and relates the factors to how a particular set up functions.

It is also a great starting point for chimney setup application for a mobile device.

One of the biggest problems with wood burning is having to rely on an expert's intuition and/or experience (real or imaginary) when selecting a stove setup initially. In my experience, a disturbing;y large proportion of these folks are full of crap or motivated by a quick payday. I'd love to see these folks (stove shop salesman/sweep 'experts') get replaced by a software application that a user can easily use to determine how well a given chimney/liner/stove combination works with their specific chimney and expected range of atmospheric and firing conditions.

A great place to start would be putting the table from the article and some what-if functionality into a cell phone app. Then you wouldn't have to rely on some bullshit artist behind a stove shop counter telling you that the manual is wrong and that it's fine to install an insert in a pre-fab fireplace (subject of another thread). Might actually save a life or two in the process...

I do agree on your point with many dealers not knowing or caring what is sold and how it is set up. But there are some very good dealers/installers also.
While some things may be a good starting point and reference, every home & setup is different. So a typical or normal setup different homes will perform differently.
A sign of a good dealer or installer, is one that works to remedy problems after the initial "typical" install. Many are never heard from again. And to be fair, others are so busy, they are backed up trying to get back to others with issues. They really should have a troubleshooting mechanic or two that works specifically on issues during the heavy season. But these days. Everything revolves around making the money, and returns for issues don't bring much revenue, unless they try to ream the homeowner a second time for bigger issues or faulty installs that some installers do not stand up to the plate for. We have a few members on here that went through such issues.
Some are lucky like myself....self install, overkill all the way, and my set up works very well. I consider myself lucky.
 
Ok been really busy with a mega scrounge (will post in the woodshed). We had a bird get into the flue...fun stuff. Starling of course. Anyway, it was nice enough to sweep for us, lol. We took the pipe off at the collar. No pics, camera problems. Not bad really. We've got about half a pie plate full, and not really much left on the inside of the pipe (no shiny stuff). We're still having the stove place out for a cleaning so they can check out the door and we can see how to clean it (baffle and brick removal).
 
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