Crimp or cinch for PEX

MikeG

I'm sure everyone has a preferred method, but is there any long term reliability  data or stories on the pros and cons of any particular PEX connection system.  I do not have much experience with PEX.  I have used it on the potable water side and some limited in the hydronic side on my own house, some repair on family members houses and some rental property.  I am about to embark on a ceiling radiant install in my own house and more in the future.  I have the tools for the copper crimp rings and the tool for the SS cinch clamps.  I have not used or do not have the tools for the expansion system.  I do try to keep it all within a single manufacturer, but ofterntimes a supplier has a mix and match.  Thanks  Mike G

CMadatMe

Wirsbo AquaPex/HePex

As long as you are not crimping of cinching this product your good. Some will post that they do and it works but not a good idea. Wirsbo/Uponor had the SSC style fittings for a very short time after they closed RTI ou on Long Island. They scrapped it because it is a potential problem on their PEX due die the fact that this PEX is produced in the Engle Method "Pex A" and has 100 percent memory.



With the expansion system the tubing itself is sucking down on the fitting that is why a Uponor/Wirsbo fitting has a larger wall than the others. When you crimp or cinch it the tubing wants to expand away from the joint to get back to it's natural state. This in the long run will lead to leaks as the crimp or cinch ring has the potential to slowly dig into the tubing.

EricAune

One tool/one manufacturer

I prefer the stainless steel press fittings from Viega.  Others will tell of other methods and manufacturers.  Uponor and Viega, in my opinion, have figured out what works the best and have produced top quality systems that are proven.



I am in Minnesota, with our lower than average winter temperatures, the Uponor expansion system can pose problem here.  During lower than desired working temperatures the rings can be quite reluctant to remember where the are are supposed to be and forget to fully contract.  This is a problem when testing (during those same low temperatures) often times requiring the use of a heat gun to make a proper joint.  This being a darned good reason to go the way of the stainless steel press fitting.