Wall Thimble Install Near Electrical Panel Question

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W.B.

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Oct 1, 2010
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MO
I started installing my through the wall kit this morning. As I mentioned in an earlier thread, this install will be located above an exterior electrical panel. As was worried about running into romex in the wall cavity and of course there are a few wires in there. Two of the wires give me enough slack to get them over to the stud and out of the way. The third however, isn't working with me. I can get the wall thimble in, but the romex touches the metal. Is this ok? I assume the whole point of the thimble is to ensure that the proper 2" clearance to combustibles is maintained in the wall cavity. So if I have some romex and some wall insulation touching the thimble (not the class a pipe) then I'm ok...right???? My instructions are pretty fuzzy on this.

Thanks for the help. I just want to make sure I'm doing a safe install.
 
I don't recall the electrical panel being mentioned in the previous posting.
https://www.hearth.com/talk/threads/through-the-wall-install.130734/#post-1761681

This sounds like there may be some code violations. The romex should be stapled before entering the panel. But more concerning from a code standpoint is the proximity of the stove and particularly the stove pipe to the panel. Usually there is a requirement for access. I think it might be 3 ft, but that is a guess. Can you post a picture of the stove location that includes the panel and thimble locations?
 
Moving this thread to the DIY section to attract some electricians. My knowledge here is rusty and I don't want to mislead. Will leave a permanent link back to the hearth forum as well.
 
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Sorry, it was mentioned in a previous post when I was trying to decide on the location. No pictures at the moment, but the pipe will exit the wall approximately 2 and a half feet above the panel. There will be plenty of room for access. I'll try to get some pictures up soon.
 
Hm, I reread that other thread and see no mention. Regardless, I suspect this is an electrical code violation based on section 110-33. Here is the section I am concerned about:
(a) Dedicated Electrical Space. The footprint space (width and depth of the equipment) extending from the floor to a height of 6 ft above the equipment or to the structural ceiling, whichever is lower, must be dedicated for the electrical installation. No piping, ducts, or other equipment foreign to the electrical installation can be installed in this dedicated footprint space. Figure 110–33

Screen Shot 2014-09-21 at 12.31.27 PM.png
 
Here is the exit with the wall flashing roughed-in.
 

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Begreen, that says indoor. Do you think that clearance requirement still applies to outdoor panels?
 
This will take a qualified electrician or electrical inspector's decision. The situation you are running into is why code calls for a dedicated space for panel wiring.The wall cavity is being used as wiring chase which is typical coming off of a panel whether indoors or not. I don't want to mislead. I'm not an electrician and haven't worked as an electrician's helper for several decades. You could be ok or maybe not so let's wait until a working electrician has a chance to comment.

Seems like it could be done safely if the wire touching the guard was extended so that it could be stapled to the stud by using a junction box higher up on the wall, but I don't know if that would pass code.
 
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I understand, appreciate your help. What about the wall insulation touching the metal on the wall thimble?
 
Not a problem, the thimble sleeve maintains the required 2" clearance. I like to remove the paper from it just for peace of mind.
 
I don't think direct contact with the thimble is going to be kosher. I passed mine through concrete so it was non-issue but a quick search seems to suggest 1-2" of air space, minimum, is required between combustibles and the thimble.

What's fuzzy about your instructions? Most codes will read, first and foremost, "must be installed per manufacturers specifications". If all else fails call the manufacturer and ask them. This would quite possibly be your most efficient path forward.
 
I've been tied up with work and haven't had time to work this out yet. The plan is to tackle it this weekend. I want to do this right, so I'm going to tear out the drywall and re-route the romex. My plan is to frame out the opening for the thimble according to the instructions. Then I'll route the romex through the stud and into the wall cavity adjacent to the stovepipe. I'll run it around the pipe before coming back into the original wall cavity and into the panel.

I bought the multi-cable spacers that will allow me to attach the romex to the studs and maintain the proper spacing. Of course, there isn't enough romex so I'm going to have to make new runs from the panel to a junction box in the wall.
 
Like BG said, you're good with the wire against the sleeve, that sleeve is your 2" clearance, the wire will be fine.

You can not bury a junction box in a wall, it needs to be accessible, so if you use one plan on making it accessible with a blank face plate.

Not sure about the clearances around the panel. I'm in the trades but not an electrician, I see stuff built around panels and meters outside all the time but that doesn't mean it's right.
 
Yes, my plan is to make it accessible with a cover plate. I'm sure that it would be fine as is, but I just won't be able to relax knowing that the wires are touching the thimble. It will not look as nice having a blank cover plate in my living room, but it will give me peace of mind.
 
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