Repipe with Pex A or Pex B controversy

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I know that using stainless threaded fittings can pose a sealing problem.

I need to use a few unions. I've only seen threaded where a male adaptor is required I've seen examples of using tape and applying it to the valley of the threads first in a string shape and then some wraps. Using PTFE stainless steel tape and/or Gray magic pipe thread compound. Not sure if tape and compound are used together.

How well does the actual stainless union mating surface seal up without galling and is a sealer used in that area?

After more research since this posting, I see there are lots of problems sealing up the threads.
 
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Use some rectorseal Teflon impregnated pipe dope.

Nothing else on the threads. No teflon tape is my preference.
 
How about the mating surface of stainless where the two union halves connect? Any problems with them leaking?

Since crimp unions or splices are available, I may use them as much as possible since repairs aren't too difficult.
 
I have had pex B installed where it went through many freeze-thaw cycles without breaking.
Expansion type, which we will say is predominately Uponor, will 1000% burst near a metal fitting. 25 years ago, in Las Vegas, I took the "Wirsbo Certified Installers Training".

The only thing that expansion type PEX has over crimp type, is the fact that it cannot be installed, without being connected. What I mean by that is crimp PEX can be put together, without crimping, hold a test, and blow off a year later.....it has happened. Expansion PEX eliminates this possibility. So for a large company, doing coutnless jobs a year, that is a big plus, all others, a waste of money.

My 3 cents.
 
Use some rectorseal Teflon impregnated pipe dope.

Nothing else on the threads. No teflon tape is my preference.
Old school........

Most these days dont realize that the teflon \ dope is merely a lube for the threads, and the threads create the seal.
 
What is there to weigh in on? You have stated some opinions and said that you had some proof to support your opinions. The only real power we have as consumers is................not to consume their products. Persoanlly I do no care what kind of pex is used, rather focus on installation "properness".
Hello Pipe Dreams, my term of weighing in was only a figure of speech. The installation correctness means nothing if the PEXa coil already has faults in the walls, which then dooms it to fail. Our application has expansion contraction while under pressure. We had no failures in the low-pressure systems, which would simulate water plumbing systems, but on the systems with a maximum pressure of 120psi, from Feb 2018 onwards, we had multiple.
If there is a defect in the PEX material wall, it becomes a matter of 'when' not 'if'.
 
Hello Pipe Dreams, my term of weighing in was only a figure of speech. The installation correctness means nothing if the PEXa coil already has faults in the walls, which then dooms it to fail. Our application has expansion contraction while under pressure. We had no failures in the low-pressure systems, which would simulate water plumbing systems, but on the systems with a maximum pressure of 120psi, from Feb 2018 onwards, we had multiple.
If there is a defect in the PEX material wall, it becomes a matter of 'when' not 'if'.
Agreed. I thoough the nature of the question was in opinions toward one or the other.

Recently, in the Charlotte area, I know of a did issue with Uponor. Several years ago, there were many QT gas stations being built, somewhere in the neighborhood of 70. They had to remove ALL Uponor PEX on the HWR (hot water return) due to failure of the pipe. Recently they have changed their products back to all white, with colored lettering.
 
So, Pex A is made by a company other than Uponor. Obviously, you trust it. Is the inner diameter of a different texture than Oponor? That's where the lawsuits are aiming.

A crimper is cheaper than a $500 expander which is a good point. Do you crimp for foolproof connections?
it is quite the opposite
 
Hello Pipe Dreams, my term of weighing in was only a figure of speech. The installation correctness means nothing if the PEXa coil already has faults in the walls, which then dooms it to fail. Our application has expansion contraction while under pressure. We had no failures in the low-pressure systems, which would simulate water plumbing systems, but on the systems with a maximum pressure of 120psi, from Feb 2018 onwards, we had multiple.
If there is a defect in the PEX material wall, it becomes a matter of 'when' not 'if'.
Also, what I mean by "my focus" is that I have no control over manufacture of the materials, and we as installers only really have sway over the installation. So as it pertains to liability, I focus on installation.
 
I use Rehau pex manufactured in Alabama and I’ve never had a failure.

Sorry you had trouble buddy but it sounds like an Australian problem. ✌️
It goes wider than that because all the PEXa from Rehau in Australia comes out of their Germany-based factory, which I understand makes all the PEXa for their Global outlets.
 
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Hello,
I based my comment on the source of production on the verbal presentation I received from the General Manager of Rehau in Australia. I know the Rehau PEXa we receive in Australia comes from Germany. The population of Australia is not big enough to justify a plant here. However, that is starting to change. The population of the USA is easily big enough to warrant a manufacturing plant to be located in the USA. Australia tends to import composite material items from either Europe or the USA.
 
I contacted our local plumbing supply house and asked about getting Pex A and fittings. I used Boshart fittings as an example.

The response was that if I wasn't using the expansion method, their users all used Viega Pex B with crimp rings and there have been no problems since they opened in 2008.

I read over this thread and didn't see any mention about Viega, so I am wondering if there are opinions about using Viega with the Boshart fittings. Besides being local, their prices are better than supplyhouse.
 
I contacted our local plumbing supply house and asked about getting Pex A and fittings. I used Boshart fittings as an example.

The response was that if I wasn't using the expansion method, their users all used Viega Pex B with crimp rings and there have been no problems since they opened in 2008.

I read over this thread and didn't see any mention about Viega, so I am wondering if there are opinions about using Viega with the Boshart fittings. Besides being local, their prices are better than supplyhouse.

I wouldn’t use it in my house but I’d use it in yours.
 
I contacted our local plumbing supply house and asked about getting Pex A and fittings. I used Boshart fittings as an example.

The response was that if I wasn't using the expansion method, their users all used Viega Pex B with crimp rings and there have been no problems since they opened in 2008.

I read over this thread and didn't see any mention about Viega, so I am wondering if there are opinions about using Viega with the Boshart fittings. Besides being local, their prices are better than supplyhouse.
as long as they meet the standard, and installed correctly, performance should be fine.
 
On a bright note, I was able to snag the crimper on ebay.

Yesterday, I stopped at a very large 1700s stone house being totally remodeled by a man who is undertaking his first "flip".

I noticed he was using pex throughout. I asked if it was A or B and he didn't know, so we looked. It's Home Depot sourced and he's using copper crimps. We didn't see any markings about A or B. I asked if he was using the go-no go gauge and he said "What's that ?"

Thanks to my new knowledge from this forum, at least I could ask some questions.
 
On a bright note, I was able to snag the crimper on ebay.

Yesterday, I stopped at a very large 1700s stone house being totally remodeled by a man who is undertaking his first "flip".

I noticed he was using pex throughout. I asked if it was A or B and he didn't know, so we looked. It's Home Depot sourced and he's using copper crimps. We didn't see any markings about A or B. I asked if he was using the go-no go gauge and he said "What's that ?"

Thanks to my new knowledge from this forum, at least I could ask some questions.

$65 shipped is a great deal.

Now, but you a tool that cuts the copper crimp rings off if you make a mistake. And you will make a mistake.

https://www.homedepot.com/p/Apollo-...VIOvjBx3hVQQzEAQYASABEgL3kfD_BwE&gclsrc=aw.ds
Nevermind the description, it works on Pex A or b. If you use copper crimp rings.

Here’s the best pex cutter sold. You need one.
https://www.homedepot.com/p/Milwauk...VjimzAB2KbAmGEAQYASABEgLVYPD_BwE&gclsrc=aw.ds
 
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Ok on the tool Recommendations. I will get them.

As far as Rehau pex, I checked everywhere and it's just not available here. R E Michel only sells it in 1000 ft rolls. I've looked everywhere.

My only option is Viega unless I shop at the big box store and I don't want to take any chances with inferior products. Not at my house.

There must be other good options, but I can't find them.
 
Ok on the tool Recommendations. I will get them.

As far as Rehau pex, I checked everywhere and it's just not available here. R E Michel only sells it in 1000 ft rolls. I've looked everywhere.

My only option is Viega unless I shop at the big box store and I don't want to take any chances with inferior products. Not at my house.

There must be other good options, but I can't find them.
Use the viega.

Make sure they store their pipe inside the building…..at the very least. If you can get them to open fresh bags of it……stick type of course. I rarely use rolls unless it’s a long run. 60+ feet
 
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Thanks for the help. I am now putting together my list and got the tools recommended.

I have Permatex thread sealant with PTFE. (80633) Is this acceptable to use with stainless fittings and should I skip tape?
 
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