Mounting A/C Disconnect to R-Panel

[rockcrawler]

I‘m searching for suggestions for the best way to mount my A/C disconnect boxes to the R-Panel siding on my shop in a way that will seal out water/air.

 

[metalmagpie]

Air conditioner or air compressor?

 

[mike93lx]

Air conditioner or air compressor?

Are the disconnects different?

 

[Leaflessshadetree]

Duct seal

 

[rockcrawler]

Air conditioner or air compressor?

Air conditioners (mini-splits)

 

[rockcrawler]

Are the disconnects different?

They are both the same. The raised holes you can see on the back of the disconnect fit between the two middle ribs on the R Panel, but they don’t completely contact the R Panel. I’ll have screws going through those three holes and then the wires from the sub panel going through the R Panel into the disconnect. I’m not sure if I will need a piece of wood on the inside of the R Panel, or if the screws will hold the disconnect to the R Panel by themselves. I just want to make sure that all the holes are sealed and don’t allow water into the shop or cause the R Panels to rust.

 

[NUTTSGT]

Is it small enough to fit between the ribs ?

 

[rockcrawler]

Duct seal

Cool. They included some of that with each of the line sets.

 

[karoc]

When I get to that stage, after I mount disconnect I will caulk the top and down both sides, but not bottom. Disconnects will stick out away from metal about 1/8-1/4 “so there will be room for caulking. But from inside I would also caulk hole where wire comes through.

 

[rockcrawler]

Is it small enough to fit between the ribs ?

The three raised screw holes barely fit between, but I think that the punch out area will end up on a rib.

 

[NUTTSGT]

I'm on my phone and just zoomed the pictures,. It's narrow enough to fit between the ribs.

Block with 2x stock or 3/4" on the inside. Mark, drill your holes and put a bead of good rtv on the back of the box. Fill the screw holes with rtv before running in the screws.

If need be, caulk around the outside edge of the box when done, mask prior to caulk. Peel tape when done and call it a day.

 

[Norcal]

When I get to that stage, after I mount disconnect I will caulk the top and down both sides, but not bottom. Disconnects will stick out away from metal about 1/8-1/4 “so there will be room for caulking. But from inside I would also caulk hole where wire comes through.

If you use the SQ D molded case switch pictured above and caulk the to & sides you will not be able to open the enclosure, due to the design of it.

 

[rockcrawler]

Thanks for the tips.

 

[dcg9381]

I use a piece of plywood to make a stand-off, I coat it in polyester resin, then paint it the color of the R-panel. Caulk around the top and both sides of the ply. I screw that through the R-panel into the girt. Then attach box to plywood.