# Pex and Compression fittings



## bfriely

I am new to pex. What is the accepted practice when using a compression Valve or fitting on Pex. I have been using the SS inserts but found out recently they are costing me about $3.50 a piece.


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## Protech

I'll answer that for ya. But first, you need to go introduce yourself like everyone else in the "introductions" area. Tell us what state(s) you work in, the code you use, the type of plumbing you do. Just get it outta the way and I'll tell ya all you want to know about it. Sorry, but rules is rules ya know?


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## bfriely

*Done*

Done


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## Airgap

bfriely said:


> Done


 No you didn't


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## bfriely

I went to my profile and made changes. Maybe didn't save. I'll check again


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## bfriely

Don't understand what else you want. Made changes to profile. Is there something else?


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## ILPlumber

http://www.plumbingzone.com/f3/ is the place for introductions. We like to "shake hands" and wheel out the welcome wagon before delving into technical talk.

After you are here for a while, you will appreciate this from other members who join.


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## Protech

OK now that the intro is done, I'll spill the beans.

Don't use brass ferrules EVER.

Use the asymmetrical pex cone ferrules with the stainless steel lock rings.

Do NOT use pipe dope or Teflon.

Make sure you tighten the nut down all the way, but don't strip the threads.

You must restrain the pipe so that thermal expansion/contraction doesn't disturb the ferrule.

Stiffeners are not required but are great insurance.

Hope this helps


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## bfriely

*Oh Crap*

That is some bad news for me. I have installed a couple dozen compression stops with brass ferrules and stainless steel insert stiffeners. I have never heard of or seen the pex asymmetrical cones with ss ribs. Are they available at Fergusons or other wholesalers? Should I go back and replace the ones I used with brass ferrules? Is there a danger they will blow off?


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## Phat Cat

Protech said:


> Don't use brass ferrules EVER.
> 
> Use the asymmetrical pex cone ferrules with the stainless steel lock rings.


Hey PT, what are the asymmetrical pex cone ferrules with stainless steel lock rings? Where do you get them?


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## Protech

YES! Go remove them and reinstall them with ether an actual crimped stop (the best way) or at least use the right ferrules. That brass ferrule is going to cut into the pipe and one day "pop"........flooded house.



bfriely said:


> That is some bad news for me. I have installed a couple dozen compression stops with brass ferrules and stainless steel insert stiffeners. I have never heard of or seen the pex asymmetrical cones with ss ribs. Are they available at Fergusons or other wholesalers? Should I go back and replace the ones I used with brass ferrules? Is there a danger they will blow off?


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## Protech

Well as I was just telling him a crimped stop is the best way for 1/2"id x 5/8"od pex (commonly referred to as 1/2"). There are also crimp adapters for 3/8"id x 1/2"od. You can get crimp on stops for that size but they are usually a special order item. The reason for that is 3/8"id x 1/2"od is typically used for manabloc systems and the valve is located back at the manabloc panel so most plumbers will not install an extra stop at the fixtures. The problem with that is many HOs want a valve under the toilet. I know that vanguard/viega make a 3/8"id x 1/2"od barbed stop. If you are willing to special order those it will be the best way to install a stop on 3/8"id x 1/2"od as no compression joint will be needed and no size adapters will be needed. 

Now for the more common 1/2"id x 5/8"od pex it's much easier. You just get a 1/2" barbed pex stop at what ever supplier you normally use. Barnett, Fergusons, Home Depot, and Lowes all stock this item.expect to pay about $10-$13 for it. 

If you must use compression there are a variety of polymer ferrules available. The ones I like the least are the symmetrical ones that replace the brass ferrule inside a standard brass compression fitting. I know fergusons stocks those. I keep them on my truck as a last resort kind of thing. The better ones are the "qicktite" style fittings for 1/2"id x 5/8"od pex.

If I’m dealing with 1/2"id x 5/8"od pex or 3/8"id x 1/2"od pex stubouts I always use an actual crimp connection. I've never had a crimp connection fail. The plastic compression ferrules work OK but I've had those develop drip later on. They aren't very resistant to leakage due to joint deflection. That's not a good thing since they are attached to a fitting that will be manhandled (the shutoff valve).

If I'm dealing with 3/8"od x 1/4"id (common supply tube size) I use the polymer ASYMETRICAL ferrules inside of standard brass compression fittings. Same thing for 1/4"od x 1/8"id (ice maker tubing size).



PlumbCrazy said:


> Hey PT, what are the asymmetrical pex cone ferrules with stainless steel lock rings? Where do you get them?


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## Protech

polymer ASYMETRICAL ferrules with stainless rings


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## Protech

crimp on stop


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## Protech

polymer ASYMETRICAL ferrules without stainless steel rings for smaller sizes


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## pauliplumber

Other than a faucet supply, what reason would you ever have to use a compression fitting with pex?


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## Protech

None. That is was what I was trying to drive home.


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## Turd Burglar

Protech said:


> crimp on stop


This is how I do them, I never use the compression fittings on pex. Only crimp rings


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## bfriely

The reason I have been using compression stops is that the crimp ring doesn't have the "finished" look of the chrome stop. Do you guys use them in exposed situations? Has anyone actually experieced a brass ferrule compression stop with an insert blowing off?
I am in the process of switching over to Uponor/Wirsbo which has it's own escutheon which houses the expansion ring. Has anyone had experience with Uponor's system?


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## Protech

Yes, I have seen compression fittings blow off. The must be installed exactly right or you’re in trouble. Do not use any pipe dope or lubricants on those connections ether.



bfriely said:


> The reason I have been using compression stops is that the crimp ring doesn't have the "finished" look of the chrome stop. Do you guys use them in exposed situations? Has anyone actually experieced a brass ferrule compression stop with an insert blowing off?
> I am in the process of switching over to Uponor/Wirsbo which has it's own escutheon which houses the expansion ring. Has anyone had experience with Uponor's system?


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## Christina

bfriely said:


> Has anyone actually experieced a brass ferrule compression stop with an insert blowing off?










I have seen these bite into poly when over tightened and actually cut the pipe. Pex closet supplies being the worst.

Suggest using the plastic farrell over the brass when applying to poly.


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## SlickRick

No brass on plastic for me...


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## bfriely

Thanks for the input everyone. No more brass on plastic for me


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## SlickRick

bfriely said:


> Thanks for the input everyone. No more brass on plastic for me


 

Your golf scores look like my Sporting Clays scores...


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## Will

I know this is an old thread, but if you read the Uponor installation guide(page 44 in mine) it says the follow regarding compression stops with there PEX.

1. Square cut the tubing perpendicular to the length of the tubing.
2. Place the nut and then the compression ring over the end the tubing.
3. Use the *BRASS* compression ring that comes with the stop
4. Install the insert into the tubing end. Be sure the insert is completely seated against the end of the tubing.
5. Wrap the threads with Teflon tape
6. Slowly tighten the compression nut to the opposing thread.

*NOTE: *Retighten all compression fittings after initial installation. Wait 30 minutes to allow the tubing to relax, and then retighten each fitting.


So to Uponor they have no issues with compression fittings with there PEX, even with SS inserts and Brass ferules. Why would a brass ferule do any more damage to the pipe from expansion than a copper crimp would? Seems to me a ferule or copper crimp ring would both have about the risk of cutting into the pipe from expansion. Or that neither would.


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## walker426

Protech said:


> Yes, I have seen compression fittings blow off. The must be installed exactly right or you&#146;re in trouble. Do not use any pipe dope or lubricants on those connections ether.


I pipe dope all of them but i install copper stubs no matter what


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## ChrisConnor

I don't see many people with brass ferrules on pex supply lines, but when I do, it's leaking.


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## DesertOkie

I never saw pex supply lines till I moved here, they all told me that the plastic rings leak. I don't use them so it's not an issue but everyone here uses brass.


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## ChrisConnor

When i used pex supplies, I never had a supply line leak using the plastic ferrules.


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## stillaround

I heard the teflon instruction when using a brass ferrule on the cpvc pipe and stop....but I never heard anything else but plastic ferrules on pex supplies...The newer supplies are stiffer


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## love2surf927

ChrisConnor said:


> I don't see many people with brass ferrules on pex supply lines, but when I do, it's leaking.


Did they use inserts?


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## piper1

i was told plastic to plastic, always no matter what. when i see pex supply line wet or dripping i'll take it apart and 90 percent of the time it has a metal furrell on pex. common under k. sinks. ho's do this alot, i hear commets like my husband put that in a couple years ago. or the tile guy just put the toilet back!!


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## ChrisConnor

love2surf927 said:


> Did they use inserts?


never.


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## love2surf927

ChrisConnor said:


> never.


Theres the issue.


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## Mississippiplum

We don't use pex supplies so it don't matter to me

sent from the jobsite porta-potty


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## ChrisConnor

love2surf927 said:


> Did they use inserts?


They make inserts?


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## Will

http://www.pexsupply.com/Viega-56120-1-2-Insert-Stiffener-for-Compression-MANABLOC-MINIBLOC


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## Joeypipes 23

Ugh must be nice to be able to run pex and not only for heating


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## ChrisConnor

Will said:


> http://www.pexsupply.com/Viega-56120-1-2-Insert-Stiffener-for-Compression-MANABLOC-MINIBLOC


I know about the ones for pipe, I was talking about the 3/8" toilet supply. I thought he was talking about that.


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## pilot light

dont use pex supplies :thumbsup:


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## Will

The PEX supplies don't need inserts if your using the delrin ferrule on the 3/8" supplies, you do need an insert though if your using the brass ferrule.


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## ChrisConnor

The only pex insert that I had seen was for icemaker line, never for toilet supplies, but I just used the plastic ferrules because brass just seemed like a bad idea in the first place, especially after seeing them cut off PB supplies. I'll just skip the brass ferrules altogether.


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## piper1

now you bought it up chris . ive always wondered why inserts only for ice lines and not other pex lines? anybody know why?


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## Joeypipes 23

Wish I had some input...but I have absolutely no experience with pex other than a staple up radiant heat job


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## Tommy plumber

piper1 said:


> now you bought it up chris . ive always wondered why inserts only for ice lines and not other pex lines? anybody know why?


 






Being in Boynton Beach, you will run into alot of Pex. They make inserts for 1/2". I've installed alot of it down there in PB county.


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## Mississippiplum

piper1 said:


> now you bought it up chris . ive always wondered why inserts only for ice lines and not other pex lines? anybody know why?


Cause that ice maker tubing is extremely thin, and so you have to be very carful w/ it.

sent from the jobsite porta-potty


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## piper1

thanks tommy, so my next question is. should i make using inserts for all pex standard procdure. or just the ice lines. now i olny use the inserts on ice, coffee lines the small stuff. never on toilets or faucets, as you said tommy its everywhere here. btw i never use copper furrells with pex. but i see it everywhere here. any suggestions or help


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## Mississippiplum

piper1 said:


> thanks tommy, so my next question is. should i make using inserts for all pex standard procdure. or just the ice lines. now i olny use the inserts on ice, coffee lines the small stuff. never on toilets or faucets, as you said tommy its everywhere here. btw i never use copper furrells with pex. but i see it everywhere here. any suggestions or help


I use inserts on all pex products. Epecially on the ice maker tubing. Unless it's being terminated with jayco or guest fittings

sent from the jobsite porta-potty


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## Tommy plumber

When I worked for a guy in the early '90s in Palm Beach county, we did new construction. We used Pex (or maybe it was Poly Butylene, I can't remember now). Anyway, we were waterpiping with the Pex without using the inserts. Then one day the boss man shows us the 1/2" stainless-steel inserts and says we need to start using them when we install the angle stops. So that's what we did from then on.


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## piper1

thanks guys, i 'll just make it part of my routine for all pex. i like it better that way, dont have to think about just, do it this way and i have no ploblem.


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## Tommy plumber

Like some of the guys already posted, with the plastic ferrules, you can omit the insert. But with a brass ferrule, you need to use the insert. The inserts stiffen up the Pex so you can use the brass ferrules.


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## piper1

so my best bet is, plastic ferrules with inserts on pex


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## Tommy plumber

I would say so. The plastic ferrule won't cut into the pipe like a brass ferrule.


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