Chimney fire after two weeks???

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Feb 27, 2022
67
Ault,CO
Alright, so here's the deal. I literally just spent months researching and taking people's thoughts and made what I thought was a good decision and purchased a BK Sirocco 30.2. Was just installed by the dealer about 3 or four weeks ago. So literally brand new. Only been burning it for two weeks or less and got the new paint smell gone and am burning on a regular basis now. Tonight the catalyst thermostat was in the inactive zone so I followed the directions and opened the bypass to start a new load after removing some ashes. Didn't think anything of it and did what the directions said (open the bypass and let it burn until the thermostat is in the active zone, then close the bypass and let it burn on high for 20-30 minutes, then set thermostat). I sat in the basement until the thermostat was just in the active zone, shut the bypass, left it on high and went out to the chicken coop to get eggs. On the way back from the coop I noticed the chimney was bellowing a thick cloud of smoke. So I stood there staring at it (its completely dark outside mind you) next thing I know I see my my chimney cap glowing like it's reflecting light from a fire in my chimney. I rushed to the door and asked my wife to listen to the chimney in the kitchen and asked if she could hear any weird whooshing sounds or pinging sounds and she said she couldn't hear anything. So I went back outside and shined a flash light up there and it was just spitting out it's normal steamy smoke that usually comes out. Went back downstairs and the thermostat wasn't even pegged out all the way yet. But I turned it down halfway anyway. So all this took place within 10-15 minutes after I shut the bypass. After this long winded explanation of my experience I guess my questions are as follows.

How on earth can I get a chimney fire after burning for a week or two? (Seasoned wood, 15-20% moisture)
What can I do to prevent this in the future?
Is this normal for a BK?
I'm a little gun shy about using it again, am I over thinking it?


P.S. I'm planning on calling the dealer on Monday to ask WTF
 
Carefully reading your post, doesn’t sound like anything happened. These things smoke like mad during warm ups. At night, that smoke looks dark. The glowing, I don’t know, did a car drive by?
 
To rule out something else (the light on the cap is concerning to me despite the remark of highbeam): how long has your wood been dried? A cat should clean up the exhaust, but does not necessarily do so well if the wood is of poor dryness.

Did you measure the moisture content?
 
Carefully reading your post, doesn’t sound like anything happened. These things smoke like mad during warm ups. At night, that smoke looks dark. The glowing, I don’t know, did a car drive by?
Our house is 1,000 feet off the road. The only way a car would make it glow is if the neighbor across the road was leaving. Which I suppose is possible. It was just strange because it sure looked like it was reflecting a fire from below. I didn't see flames but it definitely was glowing orange/yellow color. It was very shocking to see.
 
  • Like
Reactions: Highbeam
To rule out something else (the light on the cap is concerning to me despite the remark of highbeam): how long has your wood been dried? A cat should clean up the exhaust, but does not necessarily do so well if the wood is of poor dryness.

Did you measure the moisture content?
I am currently burning stuff left over from last year. Last year it measured 20% on the nose. Been sitting in the basement for a month so it's not wet from being outside in the weather at this point. Elm, pine, silver poplar, and cottonwood.
 
To rule out something else (the light on the cap is concerning to me despite the remark of highbeam): how long has your wood been dried? A cat should clean up the exhaust, but does not necessarily do so well if the wood is of poor dryness.

Did you measure the moisture content?
I am planning on splitting some today sometime to double check. I'll keep you posted.
 
  • Like
Reactions: stoveliker
Likely it's good. But double checking is better 😜
 
It’s only been a few weeks of burning. Are you confident that the flue was clean before the new stove went in?
 
Ok, so here's what I've got. Checked my wood(split a few pieces and checked on the fresh splits) 13-16%. Wood is good! Took apart my flue... yuck. I'm pretty sure I had a fire. It's all just black powdery soot now but there is definitely some shiny flakes that makes me think I did have a fire. As to respond to Highbeam, brand new flue, never been used until now.

20221120_160605.jpg 20221120_160727.jpg 20221120_160943.jpg 20221120_160952.jpg 20221120_161031.jpg 20221120_161045.jpg
 
I'm not sure that looks like evidence of a fire. Did you find flakes outside?

Surely dirty for a short time burning.
 
I guess I'm not sure what's going on. My wood is good. Burning like the directions say.
Maybe I have a bad cat thermostat? Maybe I'm burning it too low?

I feel like I should be able to burn on low setting as it is in the basement and doesn't require a ton of heat all the time. My stack is pretty tall approximately 28-29 feet top of stove to cap.
 
How deep did you get the pins in the wood?

28-29 ft may have a lot of draft, you likely need a key damper. A high draft will pull exhaust thru the cat too quickly, diminishing the effectivity of the cat.

Do you have a flue probe thermometer?
 
  • Like
Reactions: woodey
How deep did you get the pins in the wood?

28-29 ft may have a lot of draft, you likely need a key damper. A high draft will pull exhaust thru the cat too quickly, diminishing the effectivity of the cat.

Do you have a flue probe thermometer?
Got the pins buried.
No probe thermometer. Dealer said it's not necessary as well as a key damper because I asked about that.
 
That's what I'm starting to think. But I don't know. The bypass was shut so I wouldn't think It would glow from the cat. Anyone know how to check draft? I've done a little checking and found a lot of people use a dwyer mark 2 and do a permanent install to keep tabs on draft. Anyone have experience with this? Also in a previous thread I was involved in it was stated the basement effect might negate a little of the higher draft from long flue. My Elevation calls for almost 18 feet of flue minimum so I'm ten feet past that. Maybe it is pulling through the combuster to fast.

Or maybe clux is on to something and nothing ever happened and I'm being paranoid. But what would cause the flakey in my chimney?
 
I don't have a cat stove, but read about them online ::-) and 2 things occur to me, since that chimney looks awful dirty already, especially if the wood is that dry, is it possible that the cat is not sealing when coming off bypass and some smoke is going past it...or maybe since there is no cat thermometer, and a newby user, is it possible that one of the early burns was too cool, the cat stalled, and is now fouled up, not working?
 
  • Haha
Reactions: Woody Stover
I would ditch that dealer, unless he measured (but he didn't because this was a new install).

Wood seems good.

Bypass closed, thus no firebox light to the top.

Brenndatomu has a good point, although I find it hard to believe that poor gasketing would lead to this much deposits.

@bholler is this evidence of a chimney fire?
 
Alright, so I spoke with a local sweep and sent him pictures, explained everything that happened and he said that he doesn't think I had a full fledged chimney fire. He said what probably happened is that running it on high just got it hot and normally those flakes would just blow out the stack, if you zoom in and look closely there are no flakes on the class A part, only the double wall. He said likely it gets really hot in the smoke chamber and I just happened to be looking up when the combuster started burning stuff off and normally I wouldn't see that. The chimney looks good according to him and I shouldn't worry about it to terribly much unless I start to see some real accumulated creosote problems. I think I'm going to try to replicate it again with a clean stack to see if I can see that glow again. If anyone else has a different opinion please let me know.
 
  • Like
Reactions: cr0
That's what I'm starting to think. But I don't know. The bypass was shut so I wouldn't think It would glow from the cat. Anyone know how to check draft? I've done a little checking and found a lot of people use a dwyer mark 2 and do a permanent install to keep tabs on draft. Anyone have experience with this? Also in a previous thread I was involved in it was stated the basement effect might negate a little of the higher draft from long flue. My Elevation calls for almost 18 feet of flue minimum so I'm ten feet past that. Maybe it is pulling through the combuster to fast.

Or maybe clux is on to something and nothing ever happened and I'm being paranoid. But what would cause the flakey in my chimney?
From what I see in that pic there absolutely is enough there to have a fire. It would be a very small one that would be extremely unlikely to cause any damage. But if you saw a glow and sparks coming out the chimney especially with the bypass closed you had a chimney fire no doubt about it.
 
From what I see in that pic there absolutely is enough there to have a fire. It would be a very small one that would be extremely unlikely to cause any damage. But if you saw a glow and sparks coming out the chimney especially with the bypass closed you had a chimney fire no doubt about it.
I did not see any sparks. Or flames shooting out the top. Just a glow that lasted for maybe 30 seconds to a minute.