Came home the other day to water running out the back door. Amazing how quickly that can change one’s composure. Pex pipe had backed out of one of those grey plastic compression fittings that I used to hook up my tankless water heater a few years ago. Luckily, it had’nt been leaking long, maybe a hundred gallons or less into an unfinished room. I can’t completely indict the fitting though, as I believe that I may have constrained the pex from being able to expand and contract. Seems pex expands/contracts about an eighth inch/ft. over a 50 deg. temperature change. I allowed large loops at either end where the pex terminated, but fastened the pex using too many fasteners (in the wrong places) and probably constrained it. The day it flooded was unseasonably cool and I guess the cone and ring were no match for the pex pipe’s desire to contract. The pipe had probably been working itself out for years. Planning on replacing all with Sharkbites ( and removing some of the fasteners), hope I’m not being foolish not buying a crimp tool. It was difficult to justify initially for a small job.
Anyway, I’m not looking for sympathy, but hopefully this post will prevent someone else from making a similar mistake; pex needs room to move – if you constrain it, it will move anyway. While it may not pull out of a crimped connection, I wonder if the gripper teeth on a Sharkbite (or any other compression/ push fit connector) would be able to hang on to it.
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I have seen those fittings fail a number of times. They are used in our area by water softener companies and the like. I had not seen them used with pex although I am sure they are marketed as a "all conditions" piece.
Pex has a couple of fastening methods that I like better. Wirsbo uses the expansion method that uses the pex's own ability to return to its original form to hold it in place over a brass (I like) or plastic (I don't) fitting. Quest uses a crimp ring over a brass (I like) or plastic (I don't) fitting. Both work well.
Even though you seem to have it anylized and figured out I still would consider a different fitting. Just my opinion though. DanT
Dan,Can you elaborate on your dislike for the plastic fittings with Wirsbo? Have you seen them fail? Just a bad feeling?I ask because both Fergusons here supplied me with plastic, even when they've had to order the parts. I was intent on getting brass fittings at first and then got to wondering what difference it would make when the pipe is plastic anyway.Hope things are well with you.Thanks,
Steve'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
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i had mixed feeling about the wirsbo plastic fittings... BUT it's the only thing thats code here... in thousands used I've never had a leak... since wirsbo is the only approved product in my area... it's all i have used (factory trained & certified installer for what it worth)
from research the wirsbo method is to me the most fool proof and fastest... we have used up to 1.5" (i think the largest they make) and zero problems...
p
Wondering how you guys would hook up pex to the tankless heater? The connections are at the bottom, about 24" from the flue, so I ran the pex right to the heater. Currently using Zurn Qick-Tite nut/cone/ring to 3/4" brass on the heater. What would be the alternative, considering that it would be nice to be able to remove the heater without cutting the pex. My plumber/neighbor, never having hooked up a tankless, said he usually runs a copper stub to tank type heaters, then transitions with a sweat to pex barb fitting. He was at a loss on a tankless heater and said he would probably resort to a Sharkbite. I was'nt able to find a 3/4" fip to 1/2" pex barb swivel fitting, only 3/4" to 3/4". I guess most people come off the water heater with 3/4" pipe.
Also, anybody know what an R20 or R25 thread is? The term was used in conjunction with pex manifold connections on a website.
R25 thread = rope thread of 25mm
Rope thread is used in heavy percussion drill rods
Just did my first tank type heater with pex. Talked to a buddy who is fairly familiar with them - electrician that does them every day. He said you need to put a copper or other metal pipe between the pex and the tank. The ones I got at the big box were IIRC 12" long and flexible. Then I used a couple of other fittings to get to the pex size. I had valves in there too. I understand that you are using a tankless heater, and would guess that the heat generated off of it would require the same or similar treatment.
As far as getting the pex in a 3/4 x 1/2 reducer, no problem. They had 'em on the shelf at Lowe's. If I were you, I would go with the pex and buy the tool, or try to rent one. Can't believe how easy it is to use the stuff.
Don K.
EJG Homes Renovations - Rentals - New Construction
I'm installing Uponor (Wirsbo) AquaPEX in my home this week. I have a standard natural gas tank water heater. Uponor sells flexible hoses that connect to the water heater on one end, and to 3/4" PEX on the other. That's what I'm using. (I had originally planned to use SharkBite fittings everywhere, but I became too concerned about their reliability. So I sprung for the Uponor expander.)
But, IIRC, the only reason Uponor states you can't run the PEX directly to the water heater is the proximity of the water heater's inlet and outlet to the flue. I believe they say that you can run the PEX all the way to the inlet and outlet on an electric water heater. Because your inlet and outlet aren't close to the flue, it seems that wouldn't be a concern.
My only other concern would be if the body of the tankless water heater around its inlet and outlet might become hot enough to cause a problem.
I don't understand one thing about what you've said: If you left loops of extra PEX where it terminates, how could contraction have caused it to pull out of the compression fitting you used?
Actually, the area around the inlet and outlet stay quite cool.
The failure occurred at an intermediate point. I have a tee between where I connected to the old copper and the connection to the water heater. I left slack at each end, but placed my tubing supports very close to the point where the loop at one end straightened and very close to the point where the tubing turned a corner. Under these conditions, I'm not sure any amount of slack would have helped. The failure was in a straight section that just did'nt have enough slack in it.
If I had a whole house to plumb, I would spring for the expander also. That was a wise decision on your part; you may have ended up spending more on the sharkbites than the tool cost.
since you guys are talking about the expander tool i thought i would get a question in. i am about to run a whole house in pex for the first time and want to do it right. so while most information makes it seem so easy some things act like you have to make sure you keep your brands seperate. and it also seems the wirsbo pex brand with the expander is considered the best, but i have seen a few items researching that say you have to be a licensed plumber to use the expansion system. anybody know anything about this, is it true, why, etc? i.m cool with buying the expander tool if its the best way to go. just want to figure everything out before i commit to a system.thanks
Any bonehead can use the expander tool properly with 5 minutes of instruction. It is a great system. We've used it for at least 10 years with many different sizes of tubing and have never had a problem.
We use it in both domestic water and heating systems.
Wirsbo doesn't want to sell to every Tom, Dick, or Harry because they are afraid their product will be installed improperly and get a bad rep.
It is by far the easiest and most reliable system for installing Pex.
You can get the expander tools off of e-bay and the Pex from Pex Supply if nobody else will sell it to you. Get instructions from somebody who used it all the time.
Should be no problems!
I've never used expander tools. Everyone here uses crimp rings. They are idiot-proof and have never had any problems. Is there an advantage to the expander system?
Well...I would not say any system is idiot proof....but I would say that it is almost impossible to screw up a Wirsbo connection.
It is so simple and cheap that I don't know how you could come up with a better system.
The main advantage, in my opinion, is that it's a system where you can make a connection in a place that is impossible to access with all the other methods.
You place the pex ring on the end of the tubing, make the expansion, and then you can stick the tubing in to the hard to reach area and make a perfect connection.
If you use these different systems every day, you will see the clear advantage to the Wirsbo method.
The hard to reach thing does sound like a real advantage. Working with a crimper requires lots of forethought so you don't work yourself into a situation where you don't have room to make the connection.
Funny how many regional differences there are in construction. I don't know why crimp rings took off here but I've never seen any thing else.
Unless you are certified to use the Uphonor system (wirsbo) the gaurantee is not valid. If it is important to you, you must fine someone who will certify you.You get out of life what you put into it......minus taxes.
Marv
I am in the process of using all Uponor(Wirsbo) PEX components in my own house. I bought the expander tool and auto-rotation adapter from local supply house that carries Uponor - Ferguson Enterprises. There are tons of tools on eBay and PexSupply.com carries a lot of Uponor stuff for a very good price.I downloaded a .pdf copy of the latest Uponor product catalog from their website. I also called the USA headquarters and asked some questions and was helped out without anyone hassling me about being "licensed". I simply look up the part numbers in the Uponor catalog and fax an order to the supply house. No confusion if you have the numbers straight from the catalog.I can't say enough good things about all the Uponor products, they are top-notch without compromise. Some fittings are a little pricey in comparison to the generic PEX stuff but the EP plastic Uponor fittings are cheap and bulletproof.A friend of mine who is a plumber by trade helped me rough-in all the supply lines a week ago. He used Viega exclusively in his former employment. He was very impressed by the Uponor expander concept and all the materials. He also stated his Viega "certification" was a joke and he basically did one connection and a factory rep gave him a piece of paper - some training.I wouldn't use any other system - maybe rehau as they use a system that Wirsbo used to and it a little more complex but along the same concept as the expansion.I wouldn't use any other method or brand if you are serious about doing a good job and making life easier on yourself to boot. The tools are pricey but the rotator makes it a breeze to do a good job. The angle stops and trim escutcheons are cool too - just flush cut the tubing after the cabinets or vanities are set, slide on the trim and do the expansion inside the trim cover, slide in the angle stop and you're set. Nice clean finished look which is sometimes difficult when stubbing out with PEX.
Instead of using a shut off valve with a uphonor male fitting, I use a steel interior sleeve and then attach a regular compression fitting (may be a unique size). That way it can be changed out later and not have to use a short supply line. It can also be swapped out by a plumber who does not have the uphonor tools.You get out of life what you put into it......minus taxes.
Marv
I looked at the Watts SS CinchClamps a while back; the advantage being that one tool fits all sizes of rings and you don't have to get the tool all the way around the ring. Whatever you do, make sure you give the PEX room to move; 1 inch/100 feet of tubing/10 deg. Leave expansion/contraction loops and don't clamp it too tightly.
Hey P,
Where abouts do you live? I'm pretty surprised to hear that only the Wisbro system is code? Do you know why that is? Don't get me wrong I love the Wisbro system and plan on using it in my own house (as soon as I'm allowed).
Daniel Neumansky
Restoring our second Victorian home this time in Alamdea CA. Check out the blog http://www.chezneumansky.blogspot.com/
Oakland CA
Crazy Homeowner-Victorian Restorer
memphis, tn why the only one? man who knows... politics? maybe Elvis approved it?
I think that they were the manufacturer that took the time and went to the building dept and proved to them that it was a proven system... maybe to the point that the way it was approved it excluded all others?
I use to get parts approved for use by the military... I wrote the specs and the testing proceedure... basicly to exclude all others... it was time consuming and costly to get a part spec'd I sure didn't do it to have someone else slip in and profit from my work... when we sold the company I kept license to "my parts" they can still sell them... but they must buy them from me... most are now obsolete... but sometimes my work then.... still pays me now...
p
Yea that's what I thought, probably no good reason other than Wisbro was smart enough to make it that way...
Daniel Neumansky
Restoring our second Victorian home this time in Alamdea CA. Check out the blog http://www.chezneumansky.blogspot.com/
Oakland CA
Crazy Homeowner-Victorian Restorer
My heartache with plastic fittings are from experience with most other types, not Wirsbo themselves. Plastics are a petroleum product and with age and time become increasingly brittle.
When you install CPVC pipe for instance it is pretty flexible and can be cut with a ratchet style cutter. 10 years later that cutter will crush the pipe and it will splinter. A saw is your only hope for a clean cut. So in general I stay away from plastic fittings and pipe usually.
We use either copper or Pex. When I taught school I taught pex and the students were encouraged to force it to fail without cutting it or burning it. Never did happen. And alway when heated up would return to it's original form. So brass it is for me. But lots of plastic out there in use. I am just one that goes with what I feel confident in. DanT
I looked at the Wirsbo system; internet consensus seems to place it at the top among professionals. Too pricey for occasional plumbers though. I'm even having a hard time justifying a crimp ring tool, knowing that it may only get used two or three times. Opinions on Sharkbites?
I bought one of these PEX crimpers that will do four sizes of Pex tubing. If you have only a few joints to do, it's dandy and cheap. I chuck up a socket in my cordless drill to run the bolts in and out of the clamp very quickly.
I've done lots of crimps with it with zero problems plus you can use it in places a handled crimper can't go, so it's great for repairs.
Check out the seller's online store in case you need to buy rings and things.
Edited 9/21/2008 5:25 am by splintergroupie
holy mackarel. Pex crimpers, which one to buy! Your link did not work, there are a whole bevy of them available on ebay. They all seemed reasonably priced.Stainless steel crimps, copper crimps, so many choices. Can you provide some direction? Gracias.
Copper rings were the only thing available when i plumbed my first house. I got set up for that and never have needed to switch. If i were a pro, i'd certainly look into the Wirsbo system, but i've never seen the system used in my area and i'd hate to have to order fittings. I've seen a few SS crimp jobs, but i was not impressed with the workmanship, so i've developed a bit of bias against them.
I also like that it's easy to saw a ring off if i make a mistake. I don't know what the procedure is on the Wirsbo system for un-doing a boo-boo.
That tool i linked to was handy-dandy for getting in tight spots, but it would be tedious to do a whole house. I found an ebay link to someone selling the item here.
I prefer the compact crimpers for copper rings, the bent-handled ones over the longer, straight handles, if you have to buy one kind. They take more hand strain to use, but they get in tighter spots. I prefer the trunk system to the home run, so...lots of tight spots to get into.
I picked up a Pocket Crimper (http://www.pexcrimper.com/) for the few 3/4" crimps I needed. It is a very well made (in Maine!) tool, and I definitely would recommend it as a great low-cost backup, or an okay primary if you've not got too many crimps.When they say you need 10" vise-grips, they really mean it. I nearly gave myself a hand-hernia trying to crimp with 7" vise-grips and that was just a 1/2" test crimp! The crimps are indistinguishable from the crimps from my Zurn crimpers.Z
Edited 4/1/2009 9:25 am ET by mackzully
Good to hear a report. I was wondering how hard that would be to use...
Hey! That looks like the future of plumbing.
Indistinguishable you say? The same rings and the final product after installed looks identical?.
Yup, it works great if you've got the hand strength. Definitely not a tool for 1000s of crimps, but for a journeyman/emergency toolkit, I think it's about perfect. It must weigh 2lbs, and the halves separate so that you can fit it into tight areas.Z