Wood Stove Chimney Fire?

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Fossenrf

New Member
Dec 20, 2022
10
Wisconsin
Sorry for the long post, I am worried I may have had a chimney fire tonight in my wood stove and am hoping for advice on whether it was minor and should be cleaned, or if I should have it inspected for significant damage.

Here was my situation: I have an older wood stove from 1993 that has been in the house since new. The flue is straight up 16’ to a 45 degree angle which then exits through the roof another 5-10’. The stove was cleaned this fall. The outside temp is around -5F which cold temps typically cause pretty strong drafts from this stove, even with the damper closed. Tonight I got home around 8:00pm and the fire in my wood stove had gone out but there were some embers remaining so I opened the damper, threw in some kindling topped with a larger log to restart the fire, and went upstairs to change. Maybe 10-15 minutes later I went down to a roaring fire, a strong metal smell, and I could tell the draft was extremely strong. I closed the damper and the thermostat on top of the fireplace read 600F. I opened the door to let some cooler air in and heard a bunch of rustling inside the flue that I assume was creosote burning/falling that stopped when I closed the door. I went outside and could see sparks exiting the chimney, but wouldn’t say it was extreme, just a few spurts here and there. Once the fire settled down I could still here some rustling inside the flue when the door was opened, but no more sparks from the chimney and eventually everything returned to normal and now there is no noise/rustling in the flue when the door is opened and the hot metal smell is gone.

I am pretty sure I had some kind of chimney fire, but how can I diagnose the severity? I plan to clean the stove tomorrow to see how dirty it is, but anything else I should look for or be worried about?
 
It sounds like you had a chimney fire. The only way to find out if there was any damage is to have a sweep run a camera down the chimney. Is the chimney metal or masonry? Is there a liner?
 
It sounds like you had a chimney fire. The only way to find out if there was any damage is to have a sweep run a camera down the chimney. Is the chimney metal or masonry? Is there a liner?
It is a metal pipe that runs up through the roof, I am not sure on the liner but I would bet there is not one. I do have a camera I could run down the chimney, is this something I could inspect myself? If so, what would I look for? There is a foot of snow on my roof so I am not sure anyone will be willing to go up there until spring now.
 
Can you share some pictures of your setup, inside and outside? Do you have single wall pipe exiting the stove running up to the chimney, or is it double wall?

How do you clean it? Do you take the stove pipes apart? If you do, take some pics of what you have as you take it apart.

Last, if you think you had a chimney fire, you should have your chimney inspected by a certified sweep before using it again. What part of Wisconsin are you in? If you are in the SE I can recommend a sweep who I have no association with other than being a satisfied customer. If you happen to be in the Vilas, Forest, or Florence County area I have another name.
 
When I was a child, my father would have a rippin' burn during the shoulder seasons. 2 per year. It was to burn out the creosote. Did this for 30+ years. Granted, that was a 1880's slate roof home, copper flashing, and a 30' masonry chimney with an insert slammed in. But the chimney is still drafting just fine to this day.
 
It is a metal pipe that runs up through the roof, I am not sure on the liner but I would bet there is not one. I do have a camera I could run down the chimney, is this something I could inspect myself? If so, what would I look for? There is a foot of snow on my roof so I am not sure anyone will be willing to go up there until spring now.

I'd say to look for signs of damage, but that'd be obvious. Big blown seams, discoloration on the outside... but its the less obvious stuff, that my untrained eyes might miss is what would keep me up at night. What if I missed something important?

Snow on a roof can actually make it easier to walk up there depending on the lower layers and type of roof. Ice dams can provide a shelf to walk on. For my business I spend a good amount on safety equipment for my guys to safely access a roof. A good sweep will have safety equipment too, and if he can get up there safely, he will.
 
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A big thing I'd be looking into is why did you have so much creosote in the chimney so early in the season? Something could be improved to make it much safer to burn.
 
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Can you share some pictures of your setup, inside and outside? Do you have single wall pipe exiting the stove running up to the chimney, or is it double wall?

How do you clean it? Do you take the stove pipes apart? If you do, take some pics of what you have as you take it apart.

Last, if you think you had a chimney fire, you should have your chimney inspected by a certified sweep before using it again. What part of Wisconsin are you in? If you are in the SE I can recommend a sweep who I have no association with other than being a satisfied customer. If you happen to be in the Vilas, Forest, or Florence County area I have another name.
I am in Vilas (Arbor Vitae). If you know a guy that would be great! It sounds like in this case it is better to be safe than sorry.

I haven’t ever taken the pipe apart to know if it is single or double wall pipe, but it looks like there are 4 or 5’ sections each held by 3 screws. Is it as simple as just removing the screws and separating from the bottom up?

I have been cleaning it with a rotary chimney cleaner that attaches to my drill, I have enough attachments I can clean from the bottom up all the way to the chimney cap.
 
A big thing I'd be looking into is why did you have so much creosote in the chimney so early in the season? Something could be improved to make it much safer to burn.
I am thinking wet wood (not freshly cut, but not properly seasoned either). I was told the delivery I received this fall was cut in 2020, but not split until this summer. I was planning to clean the flue next week when I am off work because of it, but didn’t think it would become an issue so quickly!
 
Log wood does not really start drying out until it has been split and stacked. The flue system should be professionally inspected to make sure it is still ok to burn in.
 
I'll add that I bought a new stove last year and didn't have the best wood at all. Some wood that was split and partially seasoned, some that was old, but freshly split. I still was able to use the stove all year by doing some creative things. First, I never put any split that was larger than 3" or so. That meant re-splitting about everything before I put it into the stove. Also, I never packed it full of splits. I always stacked the splits criss-cross so that lots of air would get around them.

Because of the poor wood I always had lots of coals on reloads. I experimented with raking the coals different places, but what I found worked best in my stove was to rake the coals all to the left side of the firebox. Place a small/ medium split N/S on the right side, then stack 2-3 splits E/W on top, then another split or two N/S on top of those. I would keep the air full open until all the logs were burning, then turn down to about 50%. Sometimes I could turn it down a little further, but I never went below about 25% (75% closed). I always kept it open enough to always see bright flames.

Finally, in late January, I discovered sawdust bricks at Rural King (Similar to the ones they sell at Tractor Supply) and those completely changed the game. I would throw a couple of those in on top of the poor wood and that worked very well getting everything buring hot.

I had the chimney swept in late summer and the guy said that it looked very clean with just some dry grey powder. This was after burning like that almost every day last winter. Obviously far from ideal, I'm sure I wasted a lot of heat up the chimney and I sure went through a lot of wood burning like that, but it didn't clog up the chimney with creosote.
 
I am thinking wet wood (not freshly cut, but not properly seasoned either). I was told the delivery I received this fall was cut in 2020, but not split until this summer. I was planning to clean the flue next week when I am off work because of it, but didn’t think it would become an issue so quickly!
That sounds like the culprit! Depending on the species it can take 2-3 years for the wood to dry. Oak gives up its water very slowly!
 
I wanted to report back after cleaning. I didn’t get at much creosote as I expected, is there any indicators in the creosote that would suggest a chimney fire? I’ll post a couple pics of the setup, a look up the flue before and after cleaning, and the pile of creosote that made its way into my stove from cleaning.

I would like to try and remove the pipe inside the house so that I can take a look at the 45 degree angle and see if I can figure anything out from there. How difficult is it? Is it just we simple as disconnecting each section or pipe that is screwed together and then reattaching when finished?

[Hearth.com] Wood Stove Chimney Fire?

[Hearth.com] Wood Stove Chimney Fire?

[Hearth.com] Wood Stove Chimney Fire?

[Hearth.com] Wood Stove Chimney Fire?

[Hearth.com] Wood Stove Chimney Fire?
 
It may have mostly burned off. Is this single-wall stovepipe? If so, that is part of the problem.
 
It is double wall pipe, I was able to figure that out while cleaning.
OK, I wasn't sure about the stovepipe in the interior. It looks a bit narrow for double-wall stove pipe but that could be the picture.
 
I am in Vilas (Arbor Vitae). If you know a guy that would be great! It sounds like in this case it is better to be safe than sorry.

I haven’t ever taken the pipe apart to know if it is single or double wall pipe, but it looks like there are 4 or 5’ sections each held by 3 screws. Is it as simple as just removing the screws and separating from the bottom up?

I have been cleaning it with a rotary chimney cleaner that attaches to my drill, I have enough attachments I can clean from the bottom up all the way to the chimney cap.
I looked into it but the guy I knew in Vilas County has retired. He retired less than a month after he did some work for me!
 
Don't know if it matters but in your flu pic it looks like there's a spot with an inward bend at the bottom of pipe. Maybe one of the screws didn't pierce the inner wall?
I noticed that too, I’m guessing it has been that way since new, but will probably try to get a screw through it to pull it tight.
 
Had Rick come out today, he determined it wasn’t a chimney fire, or at least there weren’t signs of a chimney fire!
If you saw sparks coming out the chimney there is no question it was a chimney fire. But probably caused no damage. You already cleaned it so really no evidence would be left unless there was damage