Pex fittings made of plastic instead of brass

[Bill Dufour]

Any opinions about pex expansion fitting made from plastic instead of brass. Things like tees, elbows, and valves. I guess modern brass is unleaded and not the same as your fathers brass. I will use indoors only with hot and cold water. Replacing old galvanized pipe before it leaks. So I AM wary of plastic since older plastic pipe users got leaks.
BILL D

[Paul F Franklin]

I have used both plastic and brass expansion fittings, Bill. I've had zero issues with either and have some that have been installed for more than 10 years. Of course that's just one small data point.

Of course, with Pex you tend to use far fewer fittings than you would with copper, so that's a plus right there.

[Jim Becker]

I doubt that current generation "plastic" products used in these applications have the same issues that "back in the day" plastic components did. PEX has quickly become the bee's knees (and for good reason including the cost of copper or acidic water's effect on copper) and if the various PEX "systems" can provide a plastic/composite product that performs as well as brass/copper at a better cost, it's what's going to become the choice. Paul also makes a good point that because PEX is typically run with many "home runs" or at least long, long pulls, far fewer connection points are going to come into play which is a good thing, regardless of what they are made of.

[Mike Soaper]

This doesn't answer your question, but this JCL link notes the differences between pex A,B,C,AL notably the bending radius

In the video at about the 5:20 mark there are demos of attaching fittings, it demos that with pexA because it's more flexible you can have larger inner dia fittings which results in higher flow. With pexB a metal crimp ring is used, with pexA the end of the pipe and a collar are mechanically stretched open then the pipe is inserted and then the pipe and collar shrink back towards their original size making a tight seal.

The Lowdown on PEX | JLC Online

[Jack Frederick]

I use Uponor Pex A for all of my work. I did my house re-pipe with it and a lot of other work since then. Also, back in the late 70’s I did a lot of Polybutylene for radiant projects. The PB pipe lasted but the Plastic fittings did not. I ended up replacing the plastic fittings with Brass and all was good. 40+ yrs later I am still reluctant to bury plastic fittings in the wall. Personal paranoia I am sure. I use the Milwaukee expanding tool for the pex A and it is excellent. I also have the Uponor manual expander set but you have to be Godzilla in heat to crank the 3/4”. I use the 90* support brackets wherever possible. They do have along radius so can be limited. Be aware that a 1/2” pex fitting, brass or plastic, has an ID of about 5/16. You do not want to go fitting, fitting, fitting as it can reduce pressure.

[Maurice Mcmurry]

There have been problems with brass and plastic.

https://www.classaction.org/pex-plumbing-lawsuit

There was a major series of losses in and around Lake Ozark MO due to Dezincification. I have been slow to get on the Pex bandwagon. If a house has copper I do not use Pex for repairs or remodeling. If I am replacing old Iron I have the home owner decide on what to use, copper or Pex. I also have doubts about Sharkbite.

[Jim Becker]

Mike makes a good point...be sure that the fittings match the PEX type being used.