Gasoline soaked barn wood?! And how to stop an overfiring stove...

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MagdalenaP

Burning Hunk
Nov 10, 2018
239
Tilbury, ON
Our neighbor demolished his 1950's barn and gave us lots of wood. We've been adding a say 6"x 12" piece or so to every fire. Today was cold, I added two, along with our usual ash firewood splits (actually, a bit of a smaller load...nothing like a very cold load before bed). The stove got hot, fast. Within about 10 minutes my single wall thermometer was right at the borderline of overfiring (500f), and even though I had everything shut right down, door closed, it stayed there for maybe 30 min, then slowly crept down.

Could it have been one piece of barn wood that had gas or something else on it?

Also, other than shutting everything closed, what are some things that can be done to slow the fire?
 
Barn wood or any bone dry wood like that will burn very hot very quickly. Make sure none of it is painted. If its lead based paint, it can become airborne w the ash every time you open the stove.
 
Counterintuitive though it may be, opening the door will cool down the flue because of the large inrush of colder air.

I would not do that if you have a chimney fire, though.
 
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Counterintuitive though it may be, opening the door will cool down the flue because of the large inrush of colder air.

I would not do that if you have a chimney fire, though.
That will work but not if you're burning hedge (osage orange).
 
Our neighbor demolished his 1950's barn and gave us lots of wood. We've been adding a say 6"x 12" piece or so to every fire. Today was cold, I added two, along with our usual ash firewood splits (actually, a bit of a smaller load...nothing like a very cold load before bed). The stove got hot, fast. Within about 10 minutes my single wall thermometer was right at the borderline of overfiring (500f), and even though I had everything shut right down, door closed, it stayed there for maybe 30 min, then slowly crept down.

Could it have been one piece of barn wood that had gas or something else on it?

Also, other than shutting everything closed, what are some things that can be done to slow the fire?

Why do you believe that 500 is over fire temps? Is that stove top temperature? If so, it is normal and actually very low compared to how many people run their stoves for heat.

Modern noncat stoves are designed to supply sufficient air to combust nearly all of the smoke generated by the fuel burning. If your fuel is very dry and releases lots of smoke it is normal for that stove to try and burn it all which raises stove temperatures higher than you might like.

None of us with modern stoves have total control. They are designed to burn clean even when we want them cooler.

Did anything on the outside glow red?Many stove manuals show 800 as overfire temperature.
 
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I think it was 500 on a single wall pipe (with a magnetic thermometer). So near 1000 in the pipe.
 
I think it was 500 on a single wall pipe (with a magnetic thermometer). So near 1000 in the pipe.
You’re right. That’s hot!

The next thing to verify is that the magnetic gauge is accurate and 18” above the stove.
 
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Because you are not measuring *in* the pipe (if you have a magnetic thermometer, and not one with a probe sticking into the pipe for which you had to drill a hole in the pipe).
 
Because you are not measuring *in* the pipe (if you have a magnetic thermometer, and not one with a probe sticking into the pipe for which you had to drill a hole in the pipe).
Gotcha. So the math would always be double?
 
Gotcha. So the math would always be double?
Only for a magnetic ("on surface") thermometer on a single wall chimney pipe is the measured temperature *about* half of the flue gas temperature.

(For a probe thermometer, for a magnetic one on double wall stove pipe, and for a magnetic one on the stove body this all won't hold.)
 
My old jotul 3 non epa would sometimes run away and hit 850f almost pining the magnetic thermometer on the single wall about 16-18" high. Yeah a bit scary. On that stove i'de spin the draft wheel closed and that would slow it down. The jouil f400, that replaced the jotul 3 with the exact same set up, can barely hit 450f with it mostly cruising between 350-400f. I think the max i could get it to would be around 500f.
 
My old jotul 3 non epa would sometimes run away and hit 850f almost pining the magnetic thermometer on the single wall about 16-18" high. Yeah a bit scary. On that stove i'de spin the draft wheel closed and that would slow it down. The jouil f400, that replaced the jotul 3 with the exact same set up, can barely hit 450f with it mostly cruising between 350-400f. I think the max i could get it to would be around 500f.
So My single wall pipe shows 250 to 275 degrees F at 18" above stove top. So the inside temp is
actually 500 to 550 F ? Stove top runs about 400 to 500 F. I take it im in good shape ?
 
So My single wall pipe shows 250 to 275 degrees F at 18" above stove top. So the inside temp is
actually 500 to 550 F ? Stove top runs about 400 to 500 F. I take it im in good shape ?
Food for thought, if your getting secondary reburn flames then your internal firebox temps are above 1100 deg f, stove top of 550 deg should yield 400 - 450 deg internal chimney 18" height
 
Food for thought, if your getting secondary reburn flames then your internal firebox temps are above 1100 deg f, stove top of 550 deg should yield 400 - 450 deg internal chimney 18" height
So Would you say that in your opinion that I am doing a good job ? I have not tried an all night burn yet. Im running a Pleasant Hearth WSL 1800 medium stove. Really dont get much in the way of secondary burn. I have checked my chimney and it has a light smokey color film on the inside. It is an outside the house chimney and I never see smoke coming out the top of the chimney.
 
Sometimes older seasoned wood will light it's been soaked in gasoline but it's just super dry. I have some wood under cover seasoned 6 years that will take off like that so I have to keep a close eye on it.
 
So Would you say that in your opinion that I am doing a good job ?
No, your still burning to low for a secondary reburn stove, especially if you dont have at least 1" of ash in the firebox.
 
So Would you say that in your opinion that I am doing a good job ? I have not tried an all night burn yet. Im running a Pleasant Hearth WSL 1800 medium stove. Really dont get much in the way of secondary burn. I have checked my chimney and it has a light smokey color film on the inside. It is an outside the house chimney and I never see smoke coming out the top of the chimney.
Yes you are. That is not to cool at all. It's about the minimum but not to cool.