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Putting unsheathed 8/3 in wall

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neurosis737

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I'm in the process of converting my carport to a garage. Last year I had air conditioning installed and they ran the electrical through my attic and then out of the house into the carport where my panel is. For the exterior run from the attic to the exterior of the carport, they stripped the outer layer of insulation and ran 8/3 in conduit down to the panel. I'm hoping to take out the conduit and re-run the 8/3 through the studs in my wall. We're looking at about 20' of wire. Right now I'm thinking of using some heat shrink to re-sleeve the stripped portion. The only other option I can think of is to put in a junction box and re-run the stripped section with 8/3 NM-B which is much pricier and more work. Thoughts? This is in California FWIW.
 
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pattenp

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I'm not visually seeing where future wire will run but I just want to throw out that nm-b is not allow on exterior in conduit. Conduit outside is considered a wet location.
 
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PCustoms

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pattenp said:
I'm not visually seeing where future wire will run but I just want to throw out that nm-b is not allow on exterior in conduit. Conduit outside is considered a wet location.
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Good point.

Re-reading, it seems the current conduit is outdoors (carport) and will be moved indoors (garage conversion).

I wonder if there is already a junction box that the OP is not aware of, and he's is actually looking at thwn in the conduit. This would make sense, otherwise the initial install has a total hack job.
 
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neurosis737

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mike93lx said:
it doesn't change that since the wires aren't individually rated.

It needs to come out and be replaced to be compliant.

What a/c system is it? Must be huge to need #8. Also, why a 4 c
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Just a very large heat pump. I wanna say 4 or 5 ton. Required a 40AMP breaker. Agreed, the 4C is a little weird to me 😂. Going to just pick up some 8/2 from the Home Despot this weekend and run it through the walls before I cover everything in drywall.
 
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Norcal

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Post the units nameplate data, minimum circuit amperes, already said that required 40A, may not require 8 AWG cable, with A/C units you wire to the minimum & breaker it to the max.
 
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wyliesdiesels

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neurosis737 said:
I'm in the process of converting my carport to a garage. Last year I had air conditioning installed and they ran the electrical through my attic and then out of the house into the carport where my panel is. For the exterior run from the attic to the exterior of the carport, they stripped the outer layer of insulation and ran 8/3 in conduit down to the panel. I'm hoping to take out the conduit and re-run the 8/3 through the studs in my wall. We're looking at about 20' of wire. Right now I'm thinking of using some heat shrink to re-sleeve the stripped portion. The only other option I can think of is to put in a junction box and re-run the stripped section with 8/3 NM-B which is much pricier and more work. Thoughts? This is in California FWIW.
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wow what hack job did this install? so much wrong with what they did.

you cant strip NM and use the conductors individually because they arent labeled. furthermore, the conductor may only be THHN rated and therefor not permitted for use outdoors.

i would be making them come back and replace it.

you cannot reuse this cable. its junk since they molested it...
 
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Norcal

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If NM sheathed cable has been stripped as described, the wire is scrap metal it has no code compliant use, and the situation is why HVAC installers should never be allowed to do electrical.
 
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dscheidt

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wyliesdiesels said:
wow what hack job did this install? so much wrong with what they did.

you cant strip NM and use the conductors individually because they arent labeled. furthermore, the conductor may only be THHN rated and therefor not permitted for use outdoors.

i would be making them come back and replace it.

you cannot reuse this cable. its junk since they molested it...
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The wire inside an NM-B cable needn't be THHN at all, and the last time I had stripped a piece apart, it wasn't. The component wires lacked the nylon coating (the clear plastic layer that gets chewed up in tight pulls) that gives thhn its oil resistance rating. NM isn't oil resistant as part of the grade, so there's no reason to expect the wires are.
 
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sparky 1971

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dscheidt said:
The wire inside an NM-B cable needn't be THHN at all, and the last time I had stripped a piece apart, it wasn't. The component wires lacked the nylon coating (the clear plastic layer that gets chewed up in tight pulls) that gives thhn its oil resistance rating. NM isn't oil resistant as part of the grade, so there's no reason to expect the wires are.
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It doesn't need to be THHN, but NEC article 334.112 states the insulation has to have a 90° C insulation. The easiest, most cost effective way for the manufacturers would be to use THHN wire since they already have it in production. It's probably also THWN as well, but since there is no requirement for the "W", we can't be sure. Pre 1984 the insulation on the conductors was TW.
 
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