Thru wall insulated pipe safe surface temperature

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Oct 22, 2014
12
NJ
Hello,

I hope everyone is doing well! I just installed a Napoleon wood stove in my kitchen. For the inside pipe I am using black double wall. 24" vertical from top of stove, then a 90 degree elbow which connects to my through wall insulated pipe. I am using Selkirk Ultra Temp Stainless Steel insulated pipe for the thru wall pipe and all the exterior chimney sections, with the Selkirk Metalbestos thru wall kit. Since I'm new at this I was curious what the outside surface wall temperature of the thru pipe should be? I want to make sure it's not to hot going through the wall to cause a fire. The thru wall kit has a 2" air space completely around the thru wall pipe wall ring. I filled in this space with fire proof insulation. I put a thermometer on top of the pipe right where in goes in the wall. It reads around 200 degrees. I just want to make sure I'm ok. It's hot to keep my hand on it.
Thank you very much for your time!
Corey
 

ABMax24

Minister of Fire
Sep 18, 2019
1,472
Grande Prairie, Alberta, Canada
200f isn't that much, mine reaches that often.

Double check your installation instructions on that through wall kit, I'm pretty sure mine stipulated that the 2" gap must be left as airspace.
 
Oct 22, 2014
12
NJ
Thank you for the reply. I'm gonna call Selkirk tomorrow about the air space on the thru wall kit. It's very confusing. Not sure if the pipe that goes thru the wall requires 2" actual air space or this space can be filled with fire stop. I filled it with fire stop because without it I can see outside around the pipe and will get a draft.
The Selkirk thru wall is kit # 206622. Also every time I light a fire the thru wall pipe is 200 degrees F. Maybe the fire stop surrounding it is making it hotter?....
Thank you and have a good night!
 
Oct 22, 2014
12
NJ
I don't want to be a pain but I was wondering if anyone could chime in on the outside skin of the insulated thru wall pipe "normal" temps? I can't find anything anywhere.
Thank you!
Corey
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,441
central pa
I don't want to be a pain but I was wondering if anyone could chime in on the outside skin of the insulated thru wall pipe "normal" temps? I can't find anything anywhere.
Thank you!
Corey
Did you call the manufacturer of the pipe? They are the only ones who would really know
 
Oct 22, 2014
12
NJ
Funny you should ask. I called them when installing the unit and they said to pack the 2" air space with fire proof insulation where the thru wall pipe slides through. I called them today and the same person remembered me and said he made a mistake telling me to do that. So I need to remove the insulation leaving a 2" airspace in the wall thimble. It's crazy. He would not comment at all about the outside skin of the insulated pipe temps. He said they do not do testing on outside surface pipe temps. Only inside pipe heat. He wouldn't even answer if the pipe should be hand warm or hot. I was just hoping someone would chime in here on there they wall pipe temp to have piece of mind.
 
Oct 22, 2014
12
NJ
Here is my Selkirk thru wall thimble. Pics are take from the inside of the house. Basically 2 questions:

1) The pic with the red arrow. Should this 2" space be air space or add fire proof insulation?

2) The pic with the yellow arrow. With no insulation in the 2" space of thimble there is a draft and a small space where I can see daylight. Should I caulk around the insulated Selkirk ultra temp ht pipe and the wall thimble plate?

Maybe the pics will make it easier to understand. Again thank you for taking time out of your day to help me. I just don't want to put it back together until I know the correct way.

4512AD12-31DD-4101-A600-EA7302074A6B.jpeg 08876483-2BC5-4A9E-A51C-B9A139B92107.jpeg
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,441
central pa
Funny you should ask. I called them when installing the unit and they said to pack the 2" air space with fire proof insulation where the thru wall pipe slides through. I called them today and the same person remembered me and said he made a mistake telling me to do that. So I need to remove the insulation leaving a 2" airspace in the wall thimble. It's crazy. He would not comment at all about the outside skin of the insulated pipe temps. He said they do not do testing on outside surface pipe temps. Only inside pipe heat. He wouldn't even answer if the pipe should be hand warm or hot. I was just hoping someone would chime in here on there they wall pipe temp to have piece of mind.
Ask to speak to someone else. They absolutely test external temps that is what's required.

That person obviously has no clue
 

ABMax24

Minister of Fire
Sep 18, 2019
1,472
Grande Prairie, Alberta, Canada
Here is my Selkirk thru wall thimble. Pics are take from the inside of the house. Basically 2 questions:

1) The pic with the red arrow. Should this 2" space be air space or add fire proof insulation?

2) The pic with the yellow arrow. With no insulation in the 2" space of thimble there is a draft and a small space where I can see daylight. Should I caulk around the insulated Selkirk ultra temp ht pipe and the wall thimble plate?

Maybe the pics will make it easier to understand. Again thank you for taking time out of your day to help me. I just don't want to put it back together until I know the correct way.

View attachment 287728 View attachment 287729

Call them back and ask about the JUSI, it is insulation designed to go in that space and limits air infiltration.

I can't say what your local codes are, but our local inspectors will fail an inspection if that gap has been siliconed. They did that to me on a gas fired unit heater for my garage, even though the stainless venting kit instructions said to silicone that gap and it even came with the silicone to do it. I pulled it off the appease them, and re did it once they left.
 
Oct 22, 2014
12
NJ
I also sent them an email earlier this morning with the same pics I posted here. They didn't respond yet. I'll reach out again tomorrow and ask for someone else.
Thank you for your time and advice!