Wall Temps with New Stove

[CentralVAWoodHeat]

I know this has been brought up before but.....

New Jotul F600. Installed in an alcove with two sides (see avatar picture). Rear of stove sits 22 inches from wall with double wall pipe and no rear heat shield. Side of stove sits 17.5 inches from wall but mostly set out in front of it. In other words, just the few rear inches of the stove actually sit in the alcove.

Walls are 1/2 inch Soapstone tile on Duroc on wood stud so Jotul considers this 'protected'.

The install guys felt very good about the install in terms of clearance and I know we are well inside what we need to be. However, I have already gotten my hearth walls up to 140F with just two firings of the stove during the afternoon and then night.

Should I worry about this? I am having them put the rear heat shield on next week just for extra belt and suspenders. I feel like I am over thinking this and just being paranoid but wanted to get everyone's feedback.

 

[toddnic]

140 degrees should not be a problem whatsoever. Living in Florida for 20 years, the attic space in my house during the summer got higher than 140 degrees (as well as the inside of a car in July and August).

 

[jatoxico]

I think the oft quoted temp in 90 above ambient. Still I don't see how you could be too safe and if you're not comfortable and you can do it I say go for the shield.

https://www.hearth.com/talk/threads/is-190-degrees-to-hot-of-a-surface-temp-for-drywall.86301/

 

[CentralVAWoodHeat]

I think the oft quoted temp in 90 above ambient. Still I don't see how you could be too safe and if you're not comfortable and you can do it I say go for the shield.

https://www.hearth.com/talk/threads/is-190-degrees-to-hot-of-a-surface-temp-for-drywall.86301/

Got it. I've read that on here before and just wanted to make sure that still holds true. Safe to say then, if my ambient temp is 75F, I would be safe up to a wall temperature of about 165.

 

[CentralVAWoodHeat]

140 degrees should not be a problem whatsoever. Living in Florida for 20 years, the attic space in my house during the summer got higher than 140 degrees (as well as the inside of a car in July and August).

Thanks for that. That was my line of thinking too. I can still touch my wall at 140F but parts of my vehicle or places around the house in the summer would burn my hand on contact. I also have a greenhouse with metal tables inside that have never set anything on them on fire in the summer.

 

[jetsam]

I can't say if that construction is legal, but I personally wouldn't worry about a surface temp of 140° too much. Soapstone is not a good thermal conductor, and Durock is around 55x worse (which is better for you). They list half inch Durock at 0.84 BTU in /(hr ft² °F).

If the studs are hitting 170°F, that's a pyrolysis concern, but they are going to be cooler than the surface temp of the soapstone because of the Durock.

 

[jatoxico]

Got it. I've read that on here before and just wanted to make sure that still holds true. Safe to say then, if my ambient temp is 75F, I would be safe up to a wall temperature of about 165.

Yes according to what is often said. Now you said that happened after just a few loads so I imagine after running 24/7 for a week it could be higher.

In any case if you're hedging then you should be fine if its been installed according to the manufacturers specs. If the expense isn't too high add the extra shield and sleep well.

 

[CentralVAWoodHeat]

Yes according to what is often said. Now you said that happened after just a few loads so I imagine after running 24/7 for a week it could be higher.

In any case if you're hedging then you should be fine if its been installed according to the manufacturers specs. If the expense isn't too high add the extra shield and sleep well.

For sure. I like to sleep well so the heat shield will be going on next Tuesday ☺.

 

[CentralVAWoodHeat]

I can't say if that construction is legal, but I personally wouldn't worry about a surface temp of 140° too much. Soapstone is not a good thermal conductor, and Durock is around 55x worse (which is better for you). They list half inch Durock at 0.84 BTU in /(hr ft² °F).

If the studs are hitting 170°F, that's a pyrolysis concern, but they are going to be cooler than the surface temp of the soapstone because of the Durock.

Makes sense. I appreciate the breakdown on that. Sounds like I have nothing to worry about then because with a wall surface temp of 140, the durock and then the studs will be decreasingly warm.

 

[Tar12]

That was my concern when considering the proper stove for me...the BK Princess Ultra with its heat shields was a no brainer for me....and I sleep and go to work with no worries...that rear heat shield will drop that wall temp a bunch.

 

[CentralVAWoodHeat]

That was my concern when considering the proper stove for me...the BK Princess Ultra with its heat shields was a no brainer for me....and I sleep and go to work with no worries...that rear heat shield will drop that wall temp a bunch.

I'm also banking on it reducing the side wall temp as well as a by product of directing more heat forward and not letting it sit in a pocket behind the stove.

 

[Tar12]

I'm also banking on it reducing the side wall temp as well as a by product of directing more heat forward and not letting it sit in a pocket behind the stove.

I bet it will...looking forwards to your new wall temps...

 

[Dieselhead]

The wood handle on the front of my stove is at approx 180 degrees verified by my IR gun. It’s been there many years and has probably been a bit hotter than that and hasn’t spontaneously combusted as of yet. It is getting darker in color on the inside. It’s about 5” off the face of the stove.

 

[RobbieB]

Please let us know when that handle burns. A real world pyrolysis forum event!

I guess that's why they went to the coil spring handles.

 

[firefighterjake]

Temps should be fine . . . but like you I like that extra measure of protection. A few years ago we took down the dry wall behind our stoves and went to a cement board and tile. It's not a lot of extra protection, but that, coupled with having installed the stove a few inches past the minimum clearance "to be on the safe side" allows me to sleep easy at night.

 

[CentralVAWoodHeat]

Temps should be fine . . . but like you I like that extra measure of protection. A few years ago we took down the dry wall behind our stoves and went to a cement board and tile. It's not a lot of extra protection, but that, coupled with having installed the stove a few inches past the minimum clearance "to be on the safe side" allows me to sleep easy at night.

Sounds like you and I did the same thing. The alcove where the stove is now used to be drywall. Before I put the stove in, we installed the Durock cement board and soapstone tile that is there now.

My side clearance is almost four inches greater than it needs to be. And, like I said, the stove side sits almost fully outside the alcove. My rear clearance will be multiple times the minimum clearance once the heat shield is on. Right now it is 3 inches greater than it needs to be on a single wall pipe system. Mine is a double wall pipe.

Can't be too safe with this stuff.