Clearance b/n electrical wires and wall thimble within wall

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TomG

New Member
Dec 10, 2010
4
SE Pennsylvania
Hello,

A dealer will be installing a Quadrafire natural gas freestanding stove that will be directly vented through the wall. Unfortunately, the spot where the vent pipe is going contains wires. I am going to move the wires out of the way as much as I can. The owners manual says that there must be a 10" x 10" square hole in the wall to accomodate the wall thimble. My question is: how far must electrical wires (inside the wall cavity) be from the wall thimble? I did not see reference to this in the installation manual. Thank you for your help!
 
The 10x10 box out is constructed out of the same size lumber as the wall framing. Nothing can be in that space except AIR and the vent pipe.

If you really had to have the wire run through there, you would want it on the bottom side, and it needs to be 1" away from the vent pipe itself. All penetrations in the box out should be sealed.
 
Wall thimbles are zero clearance on the outside so a wire running vertical up the stud will be fine.

The top will be the hottest sides and bottom are fine. Can't be on the inside of the firestop.

If its possible, put a thin piece of roxul between the outside of the wall thimble and the wire for added piece of mind.
 
Oh yeah, I was only thinking of a horizontal wire. As he said, a vertical wire on a stud should be fine as long as it is outside the thimble which will be over 1" away on the side. A lot of the new pipe does not even have thimbles anymore, the framed out box becomes the thimble, in which case the 1" clearance on sides is still the same.
 
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