Unfortunately I'm one of those people in Colorado that has to burn a lot of pine. Tonight after I had a good bed of coals going in my Hearthstone Homestead I threw in a split that seemed to have a lot of sap on it and it exploded like you threw gas on the fire. The temperature climbed up to 500 degrees fairly quickly. I bought a new Raytec infrared thermometer to check wall temperatures and the side wall was reading 187 degrees and room temperature was 83 degrees. The interesting thing is that at that temperature I could still put my hand on the wall. The steamer on top of the stove was at 190 degrees and I could just touch my hand to it for a couple of seconds and I had to remove it. How come? Also, is this wall temperature too hot? I installed the stove according to specs of 16" from the stove to the wall.
Wall temperature too hot?
- Thread starter rdrcr56
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You are certainly at the upper range of allowable temperature. I suspect the thermomter if you could touch the wall at that temp - 190 should be too hot to touch.
Is the wall sheetrock?
The standard is 90 degrees about room air temp, which would put yours at 173....but then again, I doubt the accuracy....perhaps reflected radiant rays make it seem hot to the laser, but the actual temp of the material may not be near that.
Is the wall sheetrock?
The standard is 90 degrees about room air temp, which would put yours at 173....but then again, I doubt the accuracy....perhaps reflected radiant rays make it seem hot to the laser, but the actual temp of the material may not be near that.
We need more info according to you manual without the rear heat shield rear clearance is 26" unprotected surfacce
side is 23 single wall pipe is 18 " in all directions
Craig is right you are pushing the upper limit of acceptable heat range
side is 23 single wall pipe is 18 " in all directions
Craig is right you are pushing the upper limit of acceptable heat range
I suspect a faulty reading on the laser. There is no way you could hold your hand on a 190 degree surface and leave it there.
The stove has the rear heat shield and bottom shield, pipe is double wall. According to the manual side wall clearance is 16 in. and rear is 7in. From the side of the stove to the sheetrock is 17in. and the rear is 8in. The temp in the rear is consistant with the temp on the side wall. My question is at that temp on the wall how come I can keep my hand on it. After I remove my hand in about 10 sec. the wall temp is about 156 deg.
rdrcr56 said:
At Fahrenheit 451 paper will burn .
187 seems to be well below that level.
I use to take natural mineral hot spring in Izee Oregon
that was 140 - 145 depending on the time of day.
That was hot to the touch but your body adapts fast.
We would stay i for 5 or 6 minutes at a time.
Concerning the faulty reading, this a new thermometor that I checked against one from my work and both are right on the same temps
It's not temperature per se that would burn your hand, but total heat energy transferred. I don't know the specific heat or thermal conductivity of sheetrock or wood vs. metal, but I'm sure both are much higher for the metal. So a 190 degree wall will hold and transfer a lot less heat energy than a 190 degree metal object. The wall is likely to be hot only on the very surface, and apparently your hand has enough thermal mass to quickly lower the temperature.
I'm not sure how this relates to the likelihood of your wall bursting into flames, however.
I'm not sure how this relates to the likelihood of your wall bursting into flames, however.
Part of this issue is minium distances. According to code NFPA 211 no distance shall be reduce further than 12" that is the maxium allowable distance to combustiables.
Point here there is no penalty for exceeding clearance distances. code also governs ambience temps differencial of not exceeding 90 degrees. Say 70 is ambience
160 would be the upper linit. True about the combustion points of wood and paper. But exposed to high heat over time the molcular structure is changed anf the flash point is lowere called pyrolasis That is the reason for the ambience code to keep it in a safe range. The poster here noted a concern. lets not dismiss it and just tell him all is fine. Argue as you may but his temps indicate reason for the concern. My advice is to keep monitoring his situation and if it keeps repeating this high temps he has to allow more clearance distance..
Code interpetation does not have to apply or accept manufactures specs. As an enforcement official, we can apply the most restrictive code. If we error, then error on the side of safety.,
Point here there is no penalty for exceeding clearance distances. code also governs ambience temps differencial of not exceeding 90 degrees. Say 70 is ambience
160 would be the upper linit. True about the combustion points of wood and paper. But exposed to high heat over time the molcular structure is changed anf the flash point is lowere called pyrolasis That is the reason for the ambience code to keep it in a safe range. The poster here noted a concern. lets not dismiss it and just tell him all is fine. Argue as you may but his temps indicate reason for the concern. My advice is to keep monitoring his situation and if it keeps repeating this high temps he has to allow more clearance distance..
Code interpetation does not have to apply or accept manufactures specs. As an enforcement official, we can apply the most restrictive code. If we error, then error on the side of safety.,
Elk are you saying that 12in. is the minimum distance that I can set the stove to the wall in the rear even if the manual says 7in is permissable? Also what would someone do if they didn't have access to a infrared thermometer and they installed their stove to spec in the manual and had this problem. I thought the manufacturer had all this figured when they wrote their spec's.
You posted a legitimate concern. An inspector can also accept manufactures tested specs or defere to the limits of code. It is his choice, however his decision must be supported by written code
I made suggestions that you keep monitoring your situation. Ultimately you have to come to grips with the safety of your installation. Not me. You are doing the right thing.
Also there may be paint on the wall covering. The paint may have a lower ignition point than, the drywall paper face. I'm just trying to make you aware of possible situations. At 156 degrees a bit warm but not yet and issue.
I made suggestions that you keep monitoring your situation. Ultimately you have to come to grips with the safety of your installation. Not me. You are doing the right thing.
Also there may be paint on the wall covering. The paint may have a lower ignition point than, the drywall paper face. I'm just trying to make you aware of possible situations. At 156 degrees a bit warm but not yet and issue.
BeGreen yeh I know 83 is pretty warm but I'm still trying to figure out how to run this stove and the weather here is just cool enough (30's-40's) to need a little heat ha-ha. Roospike yes it does have the heatshield installed. Also I called hearthstone this morning and asked about this and they said to use 117 deg. as the max temp of the wall over ambient temp.
You could always buy a blower fan to sit on the floor and point it up between the heat shield and the stove to move air around.rdrcr56 said:
https://www.hearth.com/econtent/index.php/forums/viewthread/4154/
Here's the way this situation has been explained to me: NFPA 211 is a code standard to be used in the absence of a test lab listing to the contrary. In the days before manufacturers began to incorporate factory shielding on their appliances, the NFPA standard of 36" rear clearance (reduceable to 12" with approved wall shielding) was the standard. This standard applied to any woodstove, and was considered safe regardless of the individual stove in question.
Nowadays, laboratory testing reveals the exact minimum clearance requirements for a given model, and the clearances established by the testing laboratory supercede the NFPA requirements. For example, all of the stoves we sell today carry UL listings that allow closer clearances than NFPA 211 standards. We deal with six different code authorities in our service area, and all will approve an installation that complies with the tested clearance requirements, regardles of how they compare to the NFPA 211 "generic" requirements.
Should a stove that is installed according to its listed clearance ever cause a clearance-related fire, that stove would lose its listing. This ensures that the clearance numbers that appear on the UL label and in the installation manual of your listed stove are adequate for safe operation.
A note about fahrenheit 451: this is the temperature at which paper burns, once ignited. That doesn't mean paper will spontaneously combust if its temperature rises to 451f in the absence of an open flame.
Nowadays, laboratory testing reveals the exact minimum clearance requirements for a given model, and the clearances established by the testing laboratory supercede the NFPA requirements. For example, all of the stoves we sell today carry UL listings that allow closer clearances than NFPA 211 standards. We deal with six different code authorities in our service area, and all will approve an installation that complies with the tested clearance requirements, regardles of how they compare to the NFPA 211 "generic" requirements.
Should a stove that is installed according to its listed clearance ever cause a clearance-related fire, that stove would lose its listing. This ensures that the clearance numbers that appear on the UL label and in the installation manual of your listed stove are adequate for safe operation.
A note about fahrenheit 451: this is the temperature at which paper burns, once ignited. That doesn't mean paper will spontaneously combust if its temperature rises to 451f in the absence of an open flame.
I'm not sure of your decor, but why don't you put up a piece of mineral board with some 1 inch spacers and a 1 inch gap at the bottom of the board. This would create a air gap from your wall. I'm sure there's more specific ways to do this.
-Mike
-Mike
I agree with the Chimneysweep - tested min. clearance and NFPA min clearance do not relate.....If a particular stove is listed for 6" from the wall, then it does not have to be 12". The 12" in in relation to the specific materials and reduction percentages contained in NFPA.
What mikedengineer said. I also have a Heritage that is well within its clearances. My back wall wasn't as hot as yours, but I mounted a piece of durock to the wall with 1" ceramic spacers. Now the non-flammable (or much less flammable - it can smolder under extreme heat) durock gets hot while the wall behind it stays completely cool to the touch. Nice cheap solution. I tiled it, it looks great, and I sleep better.
The first thing to think about is that infared thermometers are accurate only for the thermisivity of the surface that they are reading.
The reading is most accurate if the surface is flat black. Beyond that at about 180 degrees a normal person can touch it and not get burned, but cannot hold their hand on the surface.
The reading is most accurate if the surface is flat black. Beyond that at about 180 degrees a normal person can touch it and not get burned, but cannot hold their hand on the surface.
- Jul 19, 2006
- 306
rdrcr56,
Something you might consider.
If that wall in question is an interior wall then get an indoor / outdoor thermometer & stick the outside probe into the wall, @ 6' off the floor, on the other side directly behind the heater's stove pipe.
Doing that will give you the inside temp, thus an accurate reading of the heat penetration.
Good luck with it,
Dave
Something you might consider.
If that wall in question is an interior wall then get an indoor / outdoor thermometer & stick the outside probe into the wall, @ 6' off the floor, on the other side directly behind the heater's stove pipe.
Doing that will give you the inside temp, thus an accurate reading of the heat penetration.
Good luck with it,
Dave
- Nov 12, 2006
- 66
Reliving an old post here.......I have a Jotul Oslo. Corner install with rear heatshield. Corners are 15 inches off the 5/8 inch sheetrock wall. The typical wall temp while the stove is cooking at 500 degrees is about 150 degrees. This is using the Harbor Freight infrared thermometer. The temp of the wall just seams hot. I am beyond the recommended clearances per Jotul. Anyone have a similar install?
Having been in an actual test lab I know how the stoves are tested
Code wise is the wall can be 90 degrees above ambient temperatures
meaning 70 +90 = 160 degrees. 150 is less than 160 that is ok. This also assumes that the stove is opperated within it normal manufactures suggested heat range.
Should you let it get hotter and exceed it listing naturally, you could exceed the 160 degrees, Again how accurate is the infared thremo?
Code wise is the wall can be 90 degrees above ambient temperatures
meaning 70 +90 = 160 degrees. 150 is less than 160 that is ok. This also assumes that the stove is opperated within it normal manufactures suggested heat range.
Should you let it get hotter and exceed it listing naturally, you could exceed the 160 degrees, Again how accurate is the infared thremo?
MrKenmore said:
I have a similar setup with the Castine w/heatshields. The back corner is 16" from the wall. Running 24/7 with peak temps at 550-650 degrees, the wall has never gotten so hot that I can't hold my hand on it.
I think that if my paper coated sheet rock was at 187 degrees I would start thinking about a heatshield. Depending on the layout - it may be easy to attach sheet metal piece to the wall with some spacers. It could be painted a color that is close to the rest of the walls. Then I would stop worrying. - also Merry Christmas everyone - Mike
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