What is the correct fastener?

[bluedog225]

I need to attach some steel brackets to a concrete wall. These will hold a shelf that I would use to mount two or three mini split compressors. The concrete wall was 10 inches thick and adequate for this purpose.

There’ll be some vibration. What’s the correct type of concrete anchor?

-epoxy-e.g. Simpson 3g with threaded rod
-sleeve anchor—e.g. Simpson sleeve all
-threaded fastener-simpson titen type
-Some type of lag shield
-something else?

I was leaning toward epoxy. I don’t know if it will creep under load over time. The wall it’s going to be mounted on doesn’t receive full western sun. But it still gets pretty warm in central Texas over the summer. The compressors themselves will also generate heat in the local area. And the right angle brackets will extent about 20”(?) from the wall to allow for 12” clearance for the compressor.

Thanks

 

[Hank11]

I’d go with epoxy and threaded rod. But I would also consider mounting them to the ground to decrease any vibration and noise transfer to the building. If you want them elevated, pour taller pads or build platforms of strut material.

 

[Mikes61]

If you are mounting the compressor on brackets above the ground, the wall clearance only needs to be at least 6” away from the wall. The compressor can draw air from below also when it’s raised above the ground.
This was specified in my Mr Cool manual of the 3 ton unit I installed a month ago in my garage.

 

[bluedog225]

If you are mounting the compressor on brackets above the ground, the wall clearance only needs to be at least 6” away from the wall. The compressor can draw air from below also when it’s raised above the ground.
This was specified in my Mr Cool manual of the 3 ton unit I installed a month ago in my garage.

That’s good to know. Makes things easier. thanks!

 

[bluedog225]

I’d go with epoxy and threaded rod. But I would also consider mounting them to the ground to decrease any vibration and noise transfer to the building. If you want them elevated, pour taller pads or build platforms of strut material.

Agreed about ground mount being easier all around. It’s remote and there are vandalism and theft concerns. Wall mount will get it 10’ or so off the ground. Along with shorter line sets to the second floor main living area. And the wall is pretty massive. Not too concerned with vibration. I guess I’ll find out.

 

[manwithtools]

If you are mounting the compressor on brackets above the ground, the wall clearance only needs to be at least 6” away from the wall. The compressor can draw air from below also when it’s raised above the ground.
This was specified in my Mr Cool manual of the 3 ton unit I installed a month ago in my garage.

The clearance to the wall varies by manufacturer and model. With a 10" thick concrete wall, vibration from a mini split compressor is the last concern you should have. You will never feel it, likely won't even hear the unit. I have mine mounted to a pole barn metal wall with 2" of spray foam insulation and I can barely hear it, for sure can't feel it.

 

[nadogail]

If I was given this problem, I would reach for Hilti Brand Quick ( or Kwick) Bolts, they have never failed me.

 

[gimpyrobb]

Tapcon

 

[NUTTSGT]

What is mentioned in the instructions by the manufacturer ?

 

[bluedog225]

What is mentioned in the instructions by the manufacturer ?

I don’t have the air conditioner yet. These are custom steel brackets. You may be referring to the distance between the outdoor unit and the wall. Knowing that I can bring it closer to certain units, I’ll shop with that in mind.

 

[CraigStu]

Is the typical epoxy mix thick enough that it won't run out of a horizontal hole in a wall?

 

[bluedog225]

Is the typical epoxy mix thick enough that it won't run out of a horizontal hole in a wall?

Simpson Set 3g can be used horizontally or vertically. There is a plug/piston to ensure proper fill.

 

[Hank11]

Is the typical epoxy mix thick enough that it won't run out of a horizontal hole in a wall?

You fill the hole, put tape over it and then push the bolt through the tape. Or fill the hole, coat the bolt, push in and tape around the bolt. But generally it is thick enough - depends on brand.

 

[PopcornSutton]

A typical expansion anchor will hold forever. I would not use a tapcon type.

 

[billp603]

I'd use some galvanized wedge anchors and consider mounting some unistrut to the building first and then mount the brackets on that. When it needs replacement in the future and the brackets are different unistrut allows easy adaptation.

 

[bluedog225]

Thanks everybody. I came across these and I was going through my fastener collection. I think they’ll work out. I generally agree on using uni strut. I’m on the fence. These are pretty stout brackets. I may just bolt them on and call it good.