Chimney fire

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Bspring

Feeling the Heat
Aug 3, 2007
370
Greenville, SC
Do most chimney fires start at the top or bottom? I have always thought the bottom because it should be hotter there but the few experiences that I have had appear to have been the top.
 
Do most chimney fires start at the top or bottom? I have always thought the bottom because it should be hotter there but the few experiences that I have had appear to have been the top.
Almost always the bottom that is where the fire is that lights it off. There are some rare occasions where an ember can get pulled up into the chimney and ignite creosote at the top but it is uncommon.
 
So what do you do if you have a chimney fire. Fire extinguisher. What are the options. How do you battle it
Shut the air off and call the fire dept. A fire extinguisher can do it but you still want the fire dept there to check for hot spots.
 
I have had 5 or 6 chimney fires over 30 yr span. Didn't have any until I got a cat stove and started burning on low.
They all started at the bottom and worked their way up the pipe. A couple started in the clean out tee at the bottom
of the pipe. The pipe from the stove to the ceiling glowed brightly. I always turned off the air and if the pipe didn't
start cooling off right away I would use a water spray bottle on the outside of the pipe to cool it. This would help
the creosote fire go out in the pipe. Usually would take 30-45 minutes for the pipe to go out. Didn't seem the harm the pipe
and am still using same pipe for 30 years. A couple times I tried throwing wet newspaper in the firebox so steam would
cool the chimney but that didn't seem to do as much good as cooling the outside of the stove pipe. Never called the FD
but I probably would have if had gone above the ceiling. I had triple wall pipe above the ceiling with 1" clearance above
the ceiling and could touch it with my hand but it was very hot. Using well seasoned wood and keeping the pipes clean keeps
it from happening. Also when its getting close to time to clean the pipe not running a real hot fire helps too.
 
but I probably would have if had gone above the ceiling.
What makes you think it was not burning above the ceiling? if it was burning for 30 to 45 mins that is a pretty major chimney fire. Have you had the whole system inspected?

I had triple wall pipe above the ceiling with 1" clearance above
the ceiling and could touch it with my hand but it was very hot.
What pipe is it that only requires 1" of clearance? Almost everything requires 2"
 
What makes you think it was not burning above the ceiling? if it was burning for 30 to 45 mins that is a pretty major chimney fire. Have you had the whole system inspected?


What pipe is it that only requires 1" of clearance? Almost everything requires 2"

I looked outside at the chimney cap and there was no sparks coming out. When cleaning it was the bottom section
where the creosote tended to accumulate. I would take the bottom section off to clean it and could see it was still fine.
It was not roaring once I turned the air off, it was just smoldering and you could hear it in the pipe and see the hot spots
in the places where it was glowing. The pipe was preway 8" triple wall with the outer pipe diameter 13.5" in diameter.
They don't make it anymore.
 
It was not roaring once I turned the air off, it was just smoldering and you could hear it in the pipe and see the hot spots
in the places where it was glowing.
If the pipe was glowing it was still burning pretty hard and still absolutely had enough heat to damage the chimney. Have you had the system inspected fully? I am still looking but have not found any old preway chimney systems that were rated for wood stove useage and only required 1" it may be there but I cant find it yet. I have found a few that were made for use with fireplaces that only needed 1' though
 
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If the pipe was glowing it was still burning pretty hard and still absolutely had enough heat to damage the chimney. Have you had the system inspected fully? I am still looking but have not found any old preway chimney systems that were rated for wood stove useage and only required 1" it may be there but I cant find it yet. I have found a few that were made for use with fireplaces that only needed 1' though
Preway was for a fireplace originally. I have inspected the upper pipe too from the ceiling and from the roof, it looks fine.
Once the air was turned off there is limited fuel (creosote) in the pipe , I think it would have gone out on its own but cooling the lower pipe seemed
to accelerate the fire going out. The lower pipe got the worst of the heat and it has been fully taken apart and cleaned several times and I am
planning on reusing it in my garage. It is still in good shape. Lower pipe is double wall with vents at the top and bottom so that is where I could see the
glowing. If I had left the draft open it probably would have done some damage but I always caught it a few seconds after it started. You can
tell when it starts , it doesn't sound right.
 
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Preway was for a fireplace originally.
Then it was never designed to handle the temperatures you have submitted it to. You really are asking for a disaster. Every time that chimney heats up you are lowering the ignition point of the surrounding wood. And the fact that the chimney is only rated to contain half the temperature that a chimney fire can produce is extremely dangerous. Do what you will with this info but you are really really gambling on a setup that is potentially very dangerous.
 
Then it was never designed to handle the temperatures you have submitted it to. You really are asking for a disaster. Every time that chimney heats up you are lowering the ignition point of the surrounding wood. And the fact that the chimney is only rated to contain half the temperature that a chimney fire can produce is extremely dangerous. Do what you will with this info but you are really really gambling on a setup that is potentially very dangerous.

Thanks for your concern, it has been running with a wood stove for 40 years now and under normal operation the outside wall of the pipe barely gets warm and the only place there is wood close to it (pipe) is where the support box is and that gives a 4th layer of protection.
So I think its safe. I am currently switching to a pellet stove so it should run a cooler from now on.
 
Thanks for your concern, it has been running with a wood stove for 40 years now and under normal operation the outside wall of the pipe barely gets warm and the only place there is wood close to it (pipe) is where the support box is and that gives a 4th layer of protection.
So I think its safe. I am currently switching to a pellet stove so it should run a cooler from now on.
Well I am glad you will be switching to pellets soon much less chance of disaster.

You do realize that I have heard the I have been doing it that way for 40 years many many times when we do fire damage evaluations for insurance right. The longer it goes the lower the ignition point gets. I am not looking to convince you I just want to make it very very clear to anyone else reading this that completely ignoring the very real and very clear dangers involved is asking for trouble.
 
Well I am glad you will be switching to pellets soon much less chance of disaster.

You do realize that I have heard the I have been doing it that way for 40 years many many times when we do fire damage evaluations for insurance right. The longer it goes the lower the ignition point gets. I am not looking to convince you I just want to make it very very clear to anyone else reading this that completely ignoring the very real and very clear dangers involved is asking for trouble.
Do you know what the typical flue temps of fireplace vs wood stove vs pellet stove?
 
Do you know what the typical flue temps of fireplace vs wood stove vs pellet stove?
typical flue temps will vary greatly based upon the appliance being used so not there is no way to answer that. But a chimney fire can easily run at a little over 2000 degrees in an open fireplace while the fire is still burning at that level the temps are knocked down allot by the huge amounts of dilution air which is why chimney made for prefab fireplaces don't need to be rated for as high of temps fire place chimney fires also tend to burn out much quicker meaning less time for heat to be transferred. Pellet stoves are completely different chimney fires while still possible are extremely rare with them. And if you are running a pellet stove through that old chimney you should run pellet vent up through it anyway so your clearances will be no issue at all.
 
I am not looking to convince you I just want to make it very very clear to anyone else reading this that completely ignoring the very real and very clear dangers involved is asking for trouble.

What's wrong with Oregun that you don't care to convince him?
 
What's wrong with Oregun that you don't care to convince him?
Generally when I get the 40 year thing from someone it is not worth my effort to try to convince them. I have been at peoples houses to inspect after a chimney fire caused a structure fire and still had guys arguing with me that the chimney was perfectly fine the way it is.
 
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Oregun, six chimney fires in 30 years! You are doing something very WRONG!
 
Actually 40 years, the first 10 years I didn't have a cat stove so no fires then.
But one chimney fire is too many!
Haven't had one in several years since I got my soot eater , before that I had to get on the roof with 12/12 pitch in the winter when the weather
was dry which isn't often in Oregon. All the fires occurred when I was trying to get the fire started so I was right there when it happened.
Now I can clean the pipe inside no matter the weather, but I already took out the wood stove as I will
be installing a pellet stove.
 
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What is the current stove on the chimney?
 
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What is the current stove on the chimney?
Yeah, I wonder how he's getting the chimney so gunked up with a cat stove? Wet wood, or what? Has this been with one cat stove, or many? How often do you sweep?
 
Ok.. so how dose one deal with a chimney fire. I am getting mine swept 2 times per year 1 mid season 1 at end of season. I dont plann on having one, but nobody dose. So if it happend what do you do besides trying to shut the air down, wet newspaper.
 
Ok.. so how dose one deal with a chimney fire. I am getting mine swept 2 times per year 1 mid season 1 at end of season. I dont plann on having one, but nobody dose. So if it happend what do you do besides trying to shut the air down, wet newspaper.
shut the air down and call the fire dept as I said before. Yes you can empty a fire extinguisher into the stove but you should still call the fire dept. They also make the flares that are supposed to put out chimney fires but they are marginally effective.
 
Surprisingly we haven't had any chimney fire calls yet this year in my town, usually we will have at least 10 -15, but so far nothing. I think between fuel oil being cheap and perhaps the drought summer / fall people have drier wood be default.
 
There was a lengthy thread about what to do in the event of runaway fires and chimney fires not too long ago and I seem recall many replies that said it was better to open the stove door and flood the system with air so that it would burn out more quickly and ultimately lower in-stove temps more quickly. Does anyone else remember that thread? Is my memory serving me correctly?