Cast Iron Rads - Tying into main supply/return lines - Nipples-Elbows

HandyFS

Can you all share some feedback on nipples and transitioning from the radiator valve/union, down to the main supply and return line?

I'm buying most of my supplies from SupplyHouse.com as a reference.

Nipples/Stubs/Elbows/Unions/and Pex Transition:

Valve and Unions:
My plan is to put a hot water radiator valve on the inlet, and a standard brass union elbow, or a 90 sweep (Black pipe, etc) for the return line. Some of the replacement radiators aren't identical size so I may need to cobble together some couplings and extra piping to extend to the supply/return line with the hope that I can use the same supply/return line holes in the wood floor. I'm planning on replacing the existing 1/2" valve and unions with new ones, either Matco-Norca brand, or Bluefin since Supplyhouse carries them both.


Stub Up Supply and Return Down Piping:
What is most ideal for material for the stubbing up, and piping back down? Is black pipe nipples,Chrome Brass Nipples, or Copper nipples ideal? Is this just a matter of preference to the material color? Are all compatible here? I may need to get a bit fancy with some 90's, 45's, or small extra nipples to make up minor space for a slightly smaller or larger radiator. Any materials to stay away from for the nipples, or are any of the options ok?

Here is an example of a brass chrome plated one which has a nice clean look to it. I know these are mostly used in showers and other finished plumbing/bathrooms, but any reason why I shouldn't use this with connecting a radiator to the supply/return?:
https://www.supplyhouse.com/Bluefin-CRN050-600-1-2-x-6-Chrome-Brass-Nipple-Lead-Free

All feedback appreciated.

HandyFS

After thinking about it more, those chrome brass ones may not be ideal and better suited for bathroom type plumbing. I think I will stock to black pipe after all. Curious if anyone has ever used the chrome stuff though.

hot_rod

A steel nipple takes household abuse better, vacuums, kids ramming toys, etc. Stainless nipples are another option, probably less $$ compared to chrome plated brass. If that is the look you want?

Panel radiators often connect with pex through the floor, and they have snap on covers for a better look and some protection for the tube.

HandyFS

hot_rod said:

A steel nipple takes household abuse better, vacuums, kids ramming toys, etc. Stainless nipples are another option, probably less $$ compared to chrome plated brass. If that is the look you want?

Panel radiators often connect with pex through the floor, and they have snap on covers for a better look and some protection for the tube.

Good points and great insight. I think I'll stick to black pipe after all. The radiator valve and union are already brass, so adding chrome to it would only look marginally better so I think I'll keep it simple and just go black pipe after all.

The other option is to just use new copper from the bottom of the nipple and coupling connect it back to the copper coming out of the tee, but it will be a lot more sweating so I may give the pex a shot.

Any thoughts on securing the nipples and piping in the basement? Since I'll be transitioning to pex for the connection between the nipple and the copper at the tee, I was considering using some type of galvanized/plastic supports that I'll be able to secure the nipple to the joists to ensure they are more secure and can help support the radiator above moving at the random chance. Any recommendations around this?

hot_rod

Unistrut, a block of 2X4, all sorts of plastic support parts.

Here is one of my favorite pex to threaded nipple fittings that can be well supported. Copper sweat, and 3/4" versions also.

3 ears to screw it to a 2X4 block below the radiator, adjust so the threaded nipple is where you want it.

HandyFS

hot_rod said:

Unistrut, a block of 2X4, all sorts of plastic support parts.

Here is one of my favorite pex to threaded nipple fittings that can be well supported. Copper sweat, and 3/4" versions also.

3 ears to screw it to a 2X4 block below the radiator, adjust so the threaded nipple is where you want it.

Wow Bob, great ideas here. That drop ear with the screw holes and some 2X4's seem like it would support it extremely well. I think this is just the idea I was looking for. Thanks!