What is PEX AB?

[stuckmotor]

Is there such a thing as PEX AB???
I think this is Pex A because the fittings that came with it are too big to go in without expanding the pipe. Is it PEX A?

If so I'd like to order a self rotating lever type PEX expander so I can install it. The expanders I see advertised say they're for specific brands of PEX. Are they really brand specific or will any brand of expander and rings work?

 

[stuckmotor]

Perhaps a better question is, am I misreading the label?

 

[Yander]

I could be wrong but I've used PEX a couple times and I never saw any distinction between PEX A and PEX AB.

The red PEX is for hot water the blue is for cold. I've spent a ton of time at the Lowe's in home Depot PEX section and don't remember that being a thing.

I'm not an expert though so maybe somebody else will know.

 

[4570Man]

I could be wrong but I've used PEX a couple times and I never saw any distinction between PEX A and PEX AB.

The red PEX is for hot water the blue is for cold. I've spent a ton of time at the Lowe's in home Depot PEX section and don't remember that being a thing.

I'm not an expert though so maybe somebody else will know.

The pex color code is only to make your work easier. It’s safe to use any color for hot or cold.

 

[B7510HSD]

PEX AB is a type of cross-linked polyethylene (PEX) pipe that is made from a blend of PEX A and PEX B materials. It is designed to offer the best of both worlds, combining the high temperature resistance of PEX A with the flexibility and ease of installation of PEX B. PEX AB is often used in hot water and hydronic heating systems, as well as in radiant floor heating systems. PEX AB pipe is installed using a variety of methods, including crimping, expansion, and push-to-connect fittings. Crimping fittings are the most common type of fitting used with PEX AB pipe. Expansion fittings are also commonly used, but they require a special tool to install. Push-to-connect fittings are the easiest type of fitting to install, but they are not as common as crimping or expansion fittings. From A Web search

 

[ponytug]

My guess is that your box contains PEX A, based on the fittings that you describe. AFAIK, there is no such thing as PEX AB, other than a Swedish company of that name. Your label doesn't actually say "PEX AB", just a part number that begins "AB".

PEX A/B/C are similar, but not identical.

• PEX A is polymerized with peroxides,
• PEX B is polymerized with silanes, and
• PEX C is polymerized by irradiation.

PEX A has somewhat less flexibility compared to PEX B. If you are using Uponor type expansion fittings, which are larger in diameter, you want PEX A.
More here;

PEX A vs. PEX B Piping: What’s the Difference? | Village Plumbing

Read our comparison of PEX A vs. PEX B piping with key properties and benefits of each. For more details, call Village Plumbing today.

villageplumbing.com

The Differences Between PEX-A, -B and -C

Developed in 1968 in Europe, PEX pipe came to the U.S. in the mid ‘80s, and for the past 15 years, it has become one of the most common materials used in residential plumbing systems. When you see PEX-A, PEX-B and PEX-C, you may wonder what the differences are between them and which one you...

www.sharkbite.com

I prefer PEX A Because the Uponor system is a full diameter system with no flow restriction at the fittings, though the PEX B fittings are easier to install in my very limited experience.

All the best,

Peter

 

[ponytug]

PEX AB is a type of cross-linked polyethylene (PEX) pipe that is made from a blend of PEX A and PEX B materials. It is designed to offer the best of both worlds, combining the high temperature resistance of PEX A with the flexibility and ease of installation of PEX B. PEX AB is often used in hot water and hydronic heating systems, as well as in radiant floor heating systems. PEX AB pipe is installed using a variety of methods, including crimping, expansion, and push-to-connect fittings. Crimping fittings are the most common type of fitting used with PEX AB pipe. Expansion fittings are also commonly used, but they require a special tool to install. Push-to-connect fittings are the easiest type of fitting to install, but they are not as common as crimping or expansion fittings. From A Web search

Do you have a reference for PEX AB?

Thanks!

Peter

 

[B7510HSD]

Peter good question I used the voice search on my phone but I sure can't find anything using google. when I search PEX AB it comes up with radiant heat information and most point to Pex B

 

[ponytug]

Peter good question I used the voice search on my phone but I sure can't find anything using google. when I search PEX AB it comes up with radiant heat information and most point to Pex B

Yea, I my Google-Fu failed me as well, which is why I asked.

Given the chemistry of the polymerization, I would be surprised if it exists as a PEX A + PEX B, as it would require something like blending some peroxide and some silanes to polymerize it with post extrusion steaming. Because of the cross linking, melting A+B doesn't work, unless you chop it very finely, at which point you lose many (all?) of the advantages of cross linked polyethylene over straight polyethylene.

I can imagine someone making a somewhat more flexible PEX A formulation, but then I don't see how the Uponor fittings would work as those function on the stiffness of the PEX A, which means it would effectively be a stiffer PEX B, but I don't see much advantage there. But I'm not an expert, and I am always willing to learn more.

All the best,

Peter

 

[MAX-24-Dean]

PEX A when deformed or kinked can be heated to get it back to a round tube.
PEX B when deformed or kinked needs to have that portion of the tubing cut, as you can't reform it.
PEX A is the go to choice for plumbers on most of the jobs I do drawing on.

PEX AL is specified on most jobs that have radiant heating.