Stainless Steel Clamps With Copper Stub-Outs

Big-Al_2

I was looking at some PEX literature today.  The Nibco Dura-PEX catalog says that the copper PEX stub-out fittings should not be attached with the stainless steel cinch clamps, only the copper crimps or stainless sleeves.  Other suppliers, like Zurn, and Watts don't have that instruction, and all three companies do offer the stainless clamps and copper stubs as part of their lines.  I'm wondering what the difference may be, especially if one used the heavier-duty stainless clamps from Murray, rather than the lighter ones from Oetiker.  The Murray clamps certainly look secure enough.



Does anybody here have any experience using the Stainless clamps on copper stub-outs?   Is it mainly an installation problem, or would there be issues down the road, even on a seemingly successful installation?

Big-Al_2

OK, I'll answer my own post.

After I posted this, I fired off an information request to Nibco.  Here's what I got from them:





"We caution against using the cinch clamps on the copper stub-outs because of installation issues that some installers have had.   It is a lot harder to get the clamp positioned over the top of the copper barbs. The other connection devices, crimp rings, and SS sleeves, seem to be more forgiving in this regard.  So to be fully safe you would want to switch out the connections. 



That  said, I am told that most problems of this type have tended to surface early on,  so if you have done a really good pressure test and have not experienced leaks then the installation was probably done well and you may be OK."



I did use the cinch clamps on a couple of copper PEX fittings recently, but I was very careful to place them properly, so I'll probably leave them in place.



I'd still be interested in what others here may have experienced.