Panel Upgrade,

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rnaelectric

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Location
Fullerton CA
Occupation
Electrical Contractor
I have a few code questions. I remove a flush-mount residential panel exterior stucco and replace it with a surface-mount panel that covers the entire cavity. I installed the Romex cables from the old panel with Romex BX connectors coming in from the back of the new panel. The inspector is calling out the conductors coming from the rear of the panel? and wants the BX connectors to be water-tight. The panel is outdoor-rated, and the knockouts are in the back of this panel. Can you assist with the code requirements?

FYI, the side of the house where it's installed has an overhang; there is no way water will ever come up 5 plus feet to flood the panel. A little stumped?
 
If I am understanding your post correctly there is a void or gap between where the old panel was and into the back of the panel? Going from flush mounted to surface mounted? So the Romex is exposed? or is it still inside the wall cavity and not exposed at all?

If so,
This one might be hard to win if the romex is exposed to the elements / exposed under the overhang. Technically romex (NM Cable) is not normally suitable for wet / damp locations. It is also hard to argue with an inspector on the idea of damp / wet / dry locations.

Allowed:
344.10(A)(1) - "For both exposed and concealed work in normally dry locations"

Not Allowed:
344.12(B)(4) - "In wet or damp locations"

Do you have a photo or something from it? Maybe it was something else?
 
Short answer that you won't want to hear is the panel doesn't belong outside. That, and there is no real way to bring the existing cables into the panel that is code compliant. There are no NM and BX connectors that are water tight. Once the cables leave the house they are considered outside and NM and BX and their connectors aren't listed for it. Many inspectors look the other way but I guess yours isn't.

I suppose that you could transition to UF cables inside the house then use watertight UF connectors to bring them into the panel. Another way would be conduit from the panel into the house to a J box where the existing cables transition to THHWN out to the panel.

-Hal
 
If you seal around the panel then will the cables then be in a dry location? How is this any different than NM cable into the back of a surface mounted box or light fixture?
 
infinity said:
If you seal around the panel then will the cables then be in a dry location? How is this any different than NM cable into the back of a surface mounted box or light fixture?
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We've debated this over and over. Many inspectors don't consider the space between the back of the panel and the house a dry location no matter how you seal it.

There is some company that makes a "bib" kind of thing that fits below the panel and covers the cables coming out and up into the panel. It's said to be code compliant.

-Hal
 
hbiss said:
We've debated this over and over. Many inspectors don't consider the space between the back of the panel and the house a dry location no matter how you seal it.

There is some company that makes a "bib" kind of thing that fits below the panel and covers the cables coming out and up into the panel. It's said to be code compliant.

-Hal
Click to expand...
The idea of requiring a watertight connector is stupid. If a watertight connector is required then the NM cable cannot be in the void in the first place.
 
Elect117 said:
If I am understanding your post correctly there is a void or gap between where the old panel was and into the back of the panel? Going from flush mounted to surface mounted? So the Romex is exposed? or is it still inside the wall cavity and not exposed at all?

If so,
This one might be hard to win if the romex is exposed to the elements / exposed under the overhang. Technically romex (NM Cable) is not normally suitable for wet / damp locations. It is also hard to argue with an inspector on the idea of damp / wet / dry locations.

Allowed:
344.10(A)(1) - "For both exposed and concealed work in normally dry locations"

Not Allowed:
344.12(B)(4) - "In wet or damp locations"

Do you have a photo or something from it? Maybe it was something else?
Click to expand...
I will get a photo and share it. The Romex is not exposed at all. It is still inside the wall, coming into the back of the new surface mount panel.
 
rnaelectric said:
I will get a photo and share it. The Romex is not exposed at all. It is still inside the wall, coming into the back of the new surface mount panel.
Click to expand...
I think we're able to envision the installation but what's puzzling is why this inspector wants watertight connectors? If the void behind the panel is a wet location the NM cable cannot be there.
 
This is my guess based on the description.

You have kind of a funky install, where you have this big boxed out cavity where the old panel went, and it’s covered by a new panel, but not sealed to the stucco in any way. It’s a goofy design, but I think the inspector is trying to figure out how to call it.

The big cavity behind your panel is a lot different that a 2” nipple coming into the back, which is how most surface mount panels are installed.

Why wasn’t the new panel a flush mount?

I’m not sure if I could come up with a specific code violation, but I would probably not do an install that way.
 
Install the NM in a LFNC sleeve in the void and LFNC fitting to panel. Either that or install UF or another wiring method listed for wet locations.
 
There nothing wrong with your install inspector a moron—- trim around it and fight him…
No violation have him pound sand

I despise flush mounts—- we only do surface and your install would be like 99 of the install around here.

How is that open cavity a problem. You would have trim it out and flash to keep water out . Just a normal stud bay. You change the location of the panel did not change the environment of that stud bay..


For the guys saying it’s wet location now how come???? If you drilled a 3-5/8 hole in the back of that wall to run cables into it no one would call it a wet location now but just cause that 3-5/8 is now like 18”x36 it’s now wet it’s just a bigger hole lol……

if it’s sealed properly it’s fine…
 
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hbiss said:
We've debated this over and over. Many inspectors don't consider the space between the back of the panel and the house a dry location no matter how you seal it.
Click to expand...
That is because the NEMA 3 panel requires air space behind, between the panel and the wall. 2023 NEC 312.2. That space is a wet area, and Romex is prohibited.
 
Fred B said:
That is because the NEMA 3 panel requires air space behind, between the panel and the wall. 2023 NEC 312.2. That space is a wet area, and Romex is prohibited.
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So then, if you trim it and seal it up are you violate UL listings cause it doesn’t have air ventilation.
And if airspace is the only issue, he’s covering up an old panel. There’s a lot of airspace back there
 
Fred B said:
That is because the NEMA 3 panel requires air space behind, between the panel and the wall. 2023 NEC 312.2. That space is a wet area, and Romex is prohibited.
Click to expand...
If the exterior of the enclosure is sealed the area behind it is no longer a wet location. Bringing NM cables into the back of panels, disconnects, bell boxes, etc is common practice and has not show to be an issue.

If you are only bringing a single or a few cables you can seal around them and not the entire enclosure.

In the OP's case if the inspector is worried about water getting behind the enclosure they should be much more worried about water entering the building then water coming into contact with the NM cables.
 
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