hot floor concern

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cc rangeley

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Jan 7, 2013
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I am enjoying my first woodstove - Jotul Rangeley recently installed. It sits on a Type 1 ember protection hearth pad, which meets Jotul requirements. Im concerned that the pad is hot under the stove and wonder if something's amiss with the bottom heat shield. A friend told me it's cool under her Vermont Castings stove, so Im now more worried. Thoughts/advice would be appreciated. Thanks.
 
Welcome to the forum. Each stove is different. Can you put your hand on the hearth below the stove briefly? If yes, for how long?
 
Welcome to the forum. Each stove is different. Can you put your hand on the hearth below the stove briefly? If yes, for how long?
The front is cool, but I stuck my stovetop thermometer on the pad beneath the hot area and it looks like it's about 150 degrees.
 
My IR shows my hearth pad about 150-160 at the hottest
 
Dunno. Stove installer sold it to us.
 
The hottest part of my hearth is the floor right in front of the door. Those tiles get really warm when I have her cuising at 650-700 which is pretty common lately. I can stand on it with my bare feet and actually enjoy it but not doubt this is the "hot spot" I do not have any idea of the actual temp but I will pute my cheap rutland therm down there to get some idea. Because I can hold my hand to it and stand on it I do not believe it is a cause for concern but I am going to keep an eye on it and feel it from the bottom(basement) for peace of mind.

***Update*** using the same therm that I set on my stove - stove is cruising at 700 tile floor out front is just above 100 to 130 depending on where it is setting on the floor. Warm but not scary hot.
 
I remember a post on here a while back talking about something similar but I can't find it. It basically said that if you can touch it without burning yourself, you're good to go.

Did a search for auto-ignition temperature of wood (assuming that's the first flammable thing the heat comes into contact with on your floor) and it comes back as 572 F. (http://www.engineeringtoolbox.com/fuels-ignition-temperatures-d_171.html)

So, assuming I'm looking at the right factor, should be good :)
 
The Isle Royale only requires ember protection, so I doubt that there is much thermal capacity of his hearth pad. It is acceptable to have about an 80F rise of wall temp over ambient room temp, so I would think the same would hold true for floor temp. Sounds like you are right at the outer edge of those temps.
 
The Isle Royale only requires ember protection, so I doubt that there is much thermal capacity of his hearth pad. It is acceptable to have about an 80F rise of wall temp over ambient room temp, so I would think the same would hold true for floor temp. Sounds like you are right at the outer edge of those temps.
The top of the ember pad is 200 degrees now in some spots. I checked the basement ceiling below & didnt feel heat, but it's a finished basement so I cant tell if the sub floor is getting hot. Since the R value of the ember pad is zero, wouldnt that 200 degrees transfer to the floor below? Im surprised such a big stove doesnt require thermal protection below. Im wondering if others would be concerned if they had a similar situation.
 
I remember a post on here a while back talking about something similar but I can't find it. It basically said that if you can touch it without burning yourself, you're good to go.

Did a search for auto-ignition temperature of wood (assuming that's the first flammable thing the heat comes into contact with on your floor) and it comes back as 572 F. (http://www.engineeringtoolbox.com/fuels-ignition-temperatures-d_171.html)

So, assuming I'm looking at the right factor, should be good :)

Many, many threads on this subject... and many academic papers on the same. The one thing that's been learned is that long-term exposure to heat as low as 150F to 200F can significantly lower the combustion temperature of wood. There are many sources pointing to numbers significantly lower than your 572F.

I suggest you read this thread, as well as the papers to which it refers: https://www.hearth.com/talk/threads/clearances-to-combustibles-theory.102329/
 
Many, many threads on this subject... and many academic papers on the same. The one thing that's been learned is that long-term exposure to heat as low as 150F to 200F can significantly lower the combustion temperature of wood. There are many sources pointing to numbers significantly lower than your 572F.
My temp is near 200F... I am trying to understand if that is "normal" for my Rangeley (for which Jotul requires ember protection only) or if my stove is malfunctioning, in which case Im not sure if I ask my installer or the dealer or Jotul for help.
 
200F on any combustable would be cause for concern... but this is the top of your floor protection, I'm assuming the combustable floor below is somewhat cooler. Can you describe the construction of the floor protection?

My Jotuls never get the floor temp in front above 100F, but those are well-sunk stone floors. It would be interesting to see what a piece of sheet metal laying on the floor in front of the stove would get to, certainly higher than 100F, but I do agree with your concern... 200F on the floor sounds awful high for an ember-only stove.
 
What temps are you running the stove at? If you are concerned about the hearth pad temps, improve the hearth. The factory requirements are just the minimums. There's no harm if you want to exceed them.
 
200° is hot for under that stove. How hot are you running the stove? Stove top temperature, flue temp? Is the bottom heat shield installed? This ships in a separate box and must be attached at installation. With the bottom heat shield the stove needs only ember protection. Without the bottom heat shield it must be on a solid concrete floor over earth only. Is the ash pan door closed and locked?

KaptJaq
 
200F on any combustable would be cause for concern... but this is the top of your floor protection, I'm assuming the combustable floor below is somewhat cooler. Can you describe the construction of the floor protection?


My Jotuls never get the floor temp in front above 100F, but those are well-sunk stone floors. It would be interesting to see what a piece of sheet metal laying on the floor in front of the stove would get to, certainly higher than 100F, but I do agree with your concern... 200F on the floor sounds awful high for an ember-only stove.

The floor protection is made by aj hearth originals for jotul products. Jotul specifies that the stove needs only a type 1 ember pad. I understand I can add more protection but I'm just wondering if what m experiencing is anticipated by jotul and considered normal in which case I wouldn't add more protection.
 
What temperature are you running the stove at? Where are you reading the 200F?
 
Jotul specifies that the stove needs only a type 1 ember pad.

Jotul specifies Type 1 only if the bottom heat shield is installed. Otherwise it is poured concrete over earth.
 
He has the bottom heat shield. That's why the original question and why I am asking where he is reading 200F.
 
Is the stove rear exit single wall pipe? How are temps in front of the stove glass on the hearth pad?
 
Bottom heat shield on the Rangeley is just a piece of sheet metal that is usually installed after the stove is uncrated. Very visible while the ash pan door is open. Mine is pretty cool under there, but I've never measuered the temps. I also have a top vent, double-wall setup so that may be why I get little to no heat under the rear of the stove as well.

Pictures of your setup would be helpful. Close-ups of the bottom of the stove and the stovepipe where it meets the stove would be great.
 
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Rear exit double wall pipe. Temp on hearth in front by glass is cool. It looks to me like bottom heat shield is in.

That's interesting. I'm wondering if a simple shield could be fabricated for the flue collar extending under the horiz. section of the double-wall? To make one I would use a 1' section of inexpensive 6", black, snaplock stove pipe mounted on spacers. Cost would be under $5.
 
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