Surface Mounted Junction Box to Flush SubPanel

timoct22 · Oct 2, 2022

I am connecting a manual transfer switch to a subpanel. In order to minimize drywall work, I am mounting the transfer switch to the surface of the drywall. The subpanel is flush mounted (even with the surface) to the drywall. There are 14 THHN wires that need to get from the junction box into the subpanel. The box is about 6 inches below the subpanel. I have drilled a 2" hole behind the junction box to be able to feed into the drywall. How can I get the wires into the subpanel?

Conduit is difficult to install and involves a 90 degree bend with a very small radius of curvature in a tight space inside the wall cavity.

I thought about converting to Romex inside the junction box to avoid the need for conduit, but the wiring coloring would be messed up.

There's not enough room for a 90 degree PVC bend.

Would it be really bad to skip the conduit over such a small distance?

Any ideas? I'm really struggling with this.

Megawatt · Oct 2, 2022

timoct22 said:
I am connecting a manual transfer switch to a subpanel. In order to minimize drywall work, I am mounting the transfer switch to the surface of the drywall. The subpanel is flush mounted (even with the surface) to the drywall. There are 14 THHN wires that need to get from the junction box into the subpanel. The box is about 6 inches below the subpanel. I have drilled a 2" hole behind the junction box to be able to feed into the drywall. How can I get the wires into the subpanel?

Conduit is difficult to install and involves a 90 degree bend with a very small radius of curvature in a tight space inside the wall cavity.

I thought about converting to Romex inside the junction box to avoid the need for conduit, but the wiring coloring would be messed up.

There's not enough room for a 90 degree PVC bend.

Would it be really bad to skip the conduit over such a small distance?

Any ideas? I'm really struggling with this.

To actually get into the flush mounted panel you need to cut some sheet rock and cut it square. After that use Carlin flex after that and if you are careful the you can reinstall the same peace of Sheetrock. You can still install peices of romex.