Replacing shut-off valve on PEX

[Dallas Beyer]

I want to replace the shut-off valves under my bathroom sink. I have 1/2" pex coming out of the wall. The current valve is connected with a compression nut.

I should be able to to remove the existing value with two wrenches, but I don't what to expect after I get it off. There is not enough pipe sticking out of the wall to cut any off, so whatever I do needs to use the existing pipe.

Do I reuse the existing compression nut?
Will there be a compression sleeve that i need to pry off and replace?
What is the best procedure?

Thanks

 

[mike fiore]

if you have no room you will have to use existing compression nut and ferrell...if you can find same valve you can remove old and take off the nut on new and screw on to existing nut. a pic would help just to see if you another option. i dont use compression on pex pex but it does work.

 

[Jamesplumbing06]

Umm so the obvious first question. Why do you have compression fittings on pex? The compression I aknow of is strictly ment for copper. Due to the hard rigid walls. If a “plumber” did this to you ? Then don’t call that guy back. They make valves for pex. That you either crimp on or expand pipe and let pipe shrink back around fitting. ( wirsbo expansion is the best). But no brass ferrules on pex. Call a company that has a reputation for being professional. Check all the valves in your house. You will wake up to a flood. All this rides on your word of compression valve. So nobody go off on info never mentioned. A brass ferrule will cut thru pex after a few years on constant vibration. Water running through pipe make a small vibration. And when your pex comes thru a sturdy structure. (Wall). Then you loose a lot of bounce. So your brass cuts faster. The only way I can imagine but not fully back up. Is if in your area. Suppliers might offer a plastic ferrule and plastic insert. But then I ask why not just put your crimp ring on and set fitting like manufacture intended. And never call that “rough in” plumber again. He is not a tech that sees the effects from years of use. Huge difference in “rough in” man and plumbing technician.

 

[Dallas Beyer]

Thanks for your help. The house was built 20 yrs ago, and I am the original owner. I am sure it was built to code. I haven't taken the old valve off, so maybe it is not a compression fitting. It could just look like one.

Maybe this picture will help.

Shut-off-valve

• Dallas Beyer
• Sep 17, 2018

 

[Jamesplumbing06]

Yeah that’s compression. Very shocked it lasted this long. Your in the same shape as everyone with poly faucet supply lines. Just waiting on it to go. Google poly supply lines floods. You will see so many horror stories of water. 20 years ? That guy may have been corrected all ready. So give him a call. But yeah what your first thread response said. There is only like 3-4 valve manufactures. 99% of the threads will fit. Just turn main off drain system. 1 wrench to hold valve still and another wrench to turn hex nut. And good luck with the compression holding. In my OPINOIN and professional experience in service for 18 years. Your gonna wake up to a flood. Or worse come home from vacation and have anew pool with a water bill you never thought possible. It’s all just a matter of when. Even with proper fittings you could be in the same boat. But I would at least install what the manufacture recommends and backs up. Good luck and god bless.

 

[TomFOhio]

Looks to me like it has a stiffner in it.

 

[Jamesplumbing06]

yeah it’s got an insert. Every poly supply line I seen cut has an insert. They have a real term. Insert or stiffener is close enough for the frog hair splitters.

 

[Dallas Beyer]

Just to close this out. I had five valves like this to replace. On the first one I carefully cut off the ferrule and replace it with a shark-bite fitting with a stiffener. For the other four I replaced the old compression valve with a new one using the existing copper ferrule ring. So far, so good.

Thanks again for all the advice.

 

[SHEPLMBR]

looks like cpvc to me