Plumbing – Do I expand or crimp pex water line, and why

pexplumbing

New construction water lines, should I use expansion on the fittings or should I crimp them?? And why- pros and cons of each. I have another question posted about proper sewer venting diagrams and information. I am currently getting ready to help a friend plumb his new construction home that he's and it's been several years since I've done plumbing for a living (a lifetime ago). CPVC was still the big thing when I quit plumbing and went to HVAC. Pex was just coming onto the scene, so I know very little. Any information is welcomed and greatly appreciated. I want to be able to –know– beyond any doubt that I can help my friend and everything will work properly for the life of his new home.

Best Answer

There are different types of PEX and different types of joining systems.

PEX A is joined by slipping a PEX collar around the PEX tubing, then temporarily expanding the end with the collar. Without delay the fitting is inserted and in a minute or two the PEX relaxes and grips the fitting. This type of fitting has a larger internal diameter than the fittings for the other types of PEX.

The other types of PEX are PEX B and PEX C. These latter two are joined without enlargement--a metal band is crimped in some systems and in other systems a metal band is simply pulled into place to secure the PEX tubing to the fitting. Each type has its strong points and weaker points.

One video https://www.youtube.com/watch?v=fhzIRHLOQ_E