Had a runaway fire this week!

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jayoldschool

New Member
Dec 20, 2018
21
Ontario Canada
I haven't been around here since last winter, simply because my fire building and stove operation has been completely trouble free. That changed a few nights ago. Napoleon 1900, btw. Came home, started a fire. One split, split down into strips, lasts an hour to make a coal bed. No paper, etc. Good starter temp in the yellow on my temp meter. Load up three decent size splits on the bottom, two more on top. Not "full", but a good load. Let it catch for awhile, then turned the air down and went upstairs for supper. I have a webcam pointed right at the meter on my pipe, btw. Wife checked the fire when walking by the stairs (split ranch), and said "the fire was out". I told her it wasn't out, it would still be hot, and it just needed a little more air. So, she opened the flue a bit (from LOW to 2 or 3). I was still eating, so I checked the web cam five minutes later. I couldn't see the needle so I rushed down the stairs to check it out. Needle was well into the OVERFIRE, approaching 800 and climbing fast. I yelled for her to turn on the blower (I have the kit on the back, it will bring temps down), but it was too late. I could hear bad noises in the pipe, and watched a little spark fall from a pipe joint on the vertical/horizontal transition. Did everything I could remember from reading on here. Opened the door all the way, shut off the air completely. Nope. Time for 911. She called, while I dumped a box of kindling. I use old plastic recycle boxes, so I began pulling logs out, throwing in the box, and running them up and out the front door. That's when things got smoky inside of course, and the alarm went off. Wife was discussing with 911, and checked the outside pipe, there were glowing embers floating down from it.

First volunteer showed up in about three minutes, had four guys in under five min when the first truck arrived. Three trucks responded. They did the throw a cup of water in and shut the door trick (that I had forgotten), and took the remaining coals and ash out in my bucket. We pulled the wall plate to check, and thankfully zero damage. I had a WETT inspection done when I bought this place, and there is nothing near the pipe. It does a 90, goes into double wall, then straight out through concrete before turning vertical outside.

After confirming no house damage, and checking for zero C02 (and my detector didn't go off, either). they got the ladder out and checked the pipe outside from top to bottom, pulling both the cap and the clean out. Said "that pipe is really clean!"

I'm really mad at myself for letting it get away. I take pride in having a good fire, done safely. This happened so fast. Please be careful out there.
 
That wasn’t a runaway fire, that was just a chimney fire. I would not open the door when you have a chimney fire! I would not remove burning logs. Shut everything tight.
 
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Sounds like enough excitement for a day. To stop accumulation in the horiz. section consider eliminating it by doing an offset with a pair of 45s and a short section of pipe.
two 45s for flue connect.jpg
 
I was so filled with panic/need to do something. Wasn't sure if it was a chimney fire or not, the gauge was gone off the scale quickly even with the draft closed completely and the blower on. I thought I only had seconds to get the temps down. That's when I decided to pull the logs. My stove burns well (with the draft on low (closed), so I don't think it would have come down quick enough.

Here's what it looks like. The vertical pipe is 24" from the wall. I don't think I can squeeze two 45s in there. Begreen (and others), what do you think? You can see my web cam on the corner of the record player.

Second pic is screen shot from the web cam so you can see what I see when I check it. I can pinch zoom right in on the meter. This was on a start up, you can see the draft pulled out.





Do I need to get everything cleaned before firing again? Fire said my outside pipe is fine. I could pull the vertical off the stove and have a look at that and the horizontal before lighting it. I don't burn 24/7. Maybe 2-4 times a week, one 4pm-midnight load after work, sometimes two loads a day on the weekend. Usually only when temps are -10C and below.
 
When was the last time you pulled the connector and cleaned it?
 
The vertical part? I haven't. I of course know that is a mistake. I have put in for a cleaning with a local company, but I will pull that and have a look before they get here.

I'll be at the local hardware store tomorrow, I'll check for 45s. Does anyone think I can pull off begreen's design with that limited horizontal run that comes out of the double wall pipe?
 
That flue thermometer is too low. Raise it up about 18" for a more accurate reading. FWIW, It takes more than seconds to cool things down based on a surface thermometer. Might take a minute or two before it finally starts declining.
Does anyone think I can pull off begreen's design with that limited horizontal run that comes out of the double wall pipe?
Looks possible to me with a 45º elbow at the wall thimble that angles down and intercepts the 45 on the vertical coming off the stove.
 
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Great. I'll get to work tomorrow. I always thought that horizontal section was stupid, and I don't like that heat shield that the previous owner screwed in place.

So, if there ever is a next time... leave door shut, slam the air closed, max the blower, and just wait?
 
Great. I'll get to work tomorrow. I always thought that horizontal section was stupid, and I don't like that heat shield that the previous owner screwed in place.

So, if there ever is a next time... leave door shut, slam the air closed, max the blower, and just wait?
Sometimes that is a good method, but one has to evaluate the situation at the moment. The best plan is to avoid it by keeping a clean flue, burning dry wood and setting a timer if one is not going to be in the room with the stove.
 
All good advice, thank you. I've learned everything from this forum, and I appreciate your time. I've done almost all well, burning at the right temps, using dry wood, checking frequently, watching in between checks with the camera, using the IR gun... but have neglected the flue obviously.

Interestingly, I just looked closer at the second picture. That timestamp is exactly when things started to get out of control. I must have accidentally taken a screenshot when I looked at the camera right before going downstairs.
 
It looks like you have plenty of wiggleroom to get the offset right and completely eliminate the horizontal section.
 
You can do this...put a 45 elbow right at the wall, then measure down to the vertical pipe, where the second 45 goes...you will obviously need to custom cut pipe(s) to length to make it all fit just right. Measure twice (or more) cut once.
A little trick to cut the pipe straight, cut a strip of paper 3-4" wide and 2' long or so (at least one side needs to be perfectly straight)...wrap it around the pipe and align the overlapped paper with itself, so that its nice and straight... and the "good" side with where you need to cut...mark all the way around...use a angle grinder with cutoff wheel to make a nice cut...clean the burrs off with a file...and wear leather gloves, or you will end up bleeding!
When done, don't forget to pin each joint with 3 screws then...and all male ends of the pipe/elbows should point down.
 
That double wall pipe protrudes into the room about 6", though. If the photobucket linked pic is blurry, click on it, that will take you directly to the good pic.

I'll rip the pipes out tomorrow morning. I have tin snips, grinders, etc. No problem working with sheetmetal. Thanks for the advice.

I'm determined to get this right. I really like my stove heat. I even have my blower wifi controlled!
 
Great. I'll get to work tomorrow. I always thought that horizontal section was stupid, and I don't like that heat shield that the previous owner screwed in place.

So, if there ever is a next time... leave door shut, slam the air closed, max the blower, and just wait?


Yes, opening the door will just have oxygen rush in there and fuel the fire. Also, taking out logs and then transporting them through your house is dangerous.

Like you said, the blower does a good job of reducing stove temps quickly .

If you absolutely need to rush to put the fire out, soak a wad of paper towels/newspaper in water, open the door chuck them in and quickly close it.
 
Hey Jay -- You may want to consider an Auber temperature meter or similar for your flue gas temps. I've had one for about 1.5 years and it is a game changer in running the stove. The Auber reads the temperature instantly and accurate to +/- a degree or two. It also has an audible high temperature alarm -- I've left mine at 900 F flue gas temp, which for me is lots of warning to cut the air and control the stove.

My probe style thermometer was not very accurate and lagged behind the actual conditions by hundreds of degrees.

@begreen recently got an Auber and his thread on starting a fire with it is great stuff. Mirrors my experience with the Auber exactly.
Check it out: https://www.hearth.com/talk/threads/starting-a-fire.179714/

I heartily recommend the Auber meter. I wouldn't want to run a stove without one again.
 
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Any reason it would be bad to install a stovepipe damper that you could shut in an emergency like this? I know they are not common anymore but it seems like a failsafe way to kill the draft if your fire is out of control...
 
Any reason it would be bad to install a stovepipe damper that you could shut in an emergency like this? I know they are not common anymore but it seems like a failsafe way to kill the draft if your fire is out of control...
It would help, but since they don't completely block the pipe, it would only slow a runaway fire to a degree...
 
If you have trouble controlling your stove chances are it is caused by excessive draft. So yes if that is the cause you should have a damper possibly 2.
 
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