PEX Tubing Recommendations

Tony_42

Is the superior product regardless of manufacturer. Stick with REHAU or Uponor. It costs more because it's better...

Brent H.

PEX Tubing Recommendations

I'm in the process of adding a couple of FHW zones to my heating system in order to heat an addition. In the past, I've always used copper since PEX wasn't available in Massachusetts. This time around, I'd like to use PEX tubing from boiler to radiator. I'm looking for suggestions on the best product that does not require a large investment in tools/crimpers. Any help would be appreciated.

Thanks.
-Brent

Yonson

Wirsbo

I have used Wirsbo heat-pex on my system with no problems. Make sure you use the proper tubing to prevent oxygen into your system. I use the expansion tool and collar. Never had any problems. The tool was almost $300. But I also use it on side jobs and my domestic lines.

Not a plumber only a homeowner of 15 years...

John_162

Viega FostaPex is the best and easiest to work with and you can't beat there press system

tony_43

outside boiler used for snow melt

i have glycol running through my boiler system, will this effect the pvc pipe, the pipe is schedule 80

Keith_42

Uponor/Wirsbo is the only tube I've used that really holds up. There is a TON of products out there, I only buy Wirsbo whenever I buy pex.

John_162

What a unique concept.
More expensive = Better quality. guess everyone needs to raise there prices and show people they are the better product

kpc_44

start a ...

new thread. don't hyjack this one.

Drew_2

Glycol & PVC

The short answer is;
Do not use propylene glycol in PVC or CPVC.

Tony_42

Here's some data John

PEX-a vs the rest

hot_rod

the Viega tube and fitting

are about the best I have used. I like pex with the aluminum layer for less expansion, better shape holding, etc. Viega offers the best of both with full diameter pex inner tube, al layer, then a protective outer coating.

hr

John_162

Another unique Ides proving a point with the info written by the manufacture of the product you claim is the best.
Now try and find a third party like the plastic institute to prove your point and maybe we will listen. it ain't going to happen

Tony_42

How about from this site? Good enough?

http://www.heatinghelp.com/newsletter.cfm?Id=18


Engel-method PEX (also known as PEX-A) This is the stuff Tomas Engel brought into the world. Engel was the guy who invented PEX. He is a European scientist and he had nothing to do with the radiant heating industry when he invented PEX. I heard him speak at a meeting in Sweden in 1990 and was fascinated by his story. But that, too, is a story for another day. What's important for you to know is that Engel-method PEX gets crosslinked while it’s still in its melted form. The manufacturers do this by adding peroxide to the mix and then applying a tremendous amount of pressure and temperature to the liquid. What comes squirting out of the machine is PEX that's as clear as glass. As it cools, it takes on a darker color. The Engel method gives the pipe an essentially uniform distribution of the crosslinking sites throughout the material. From what I’ve read in independent scientific papers that have come from Europe, this is the best way to make PEX. It takes a while longer to do it this way, and this sort of PEX may cost a bit more.



Irradiation-method PEX (also known as PEX-C) Irradiated PEX starts out as straight polyethylene tubing. As with other methods of making straight polyethylene, the tubing takes on a definite form during the extrusion process. With the irradiation method, the crosslinking takes place in a second process when the manufacturer runs the tubing through an electron beam cannon. The beam gets the polyethylene molecules so excited that they crosslink.



This method can sometimes result in a less uniform crosslinking of the material, however, especially if the pipe is larger than 1" in diameter. This happens because the thicker pipe requires a higher dose of radiation. If it’s not done properly, the outer layer of irradiated PEX can become brittle, but this is not a concern in a well-controlled process. If the pipe maker is experienced there is no need for concern with this sort of PEX when used on a radiant heating system. Buy in the mainstream and you'll do fine.



Silane-method PEX (also known as PEX-B) The big difference between this method and the other two methods is that with the Engel and Irradiation methods, the crosslinking consists of a bond between carbon molecules. With the Silane method the crosslinking takes place across silicon and oxygen molecules. These links are weaker than the carbon-carbon links that result from the other methods, and this may have an effect on the long-term chemical stability of the material. If we live long enough, we’ll probably find out.



I hope all this chemistry isn't making your head spin. I think it's good for you to know the differences between these materials even though they all go under the name PEX. Let's face it, you're the one who’s going to be putting the tubing under the floor.



In fairness, though, I have to tell you that none of these methods is a bad method; The American Society for Testing and Materials (ASTM) approves all three methods. However, in a world among "equals," it seems to me that some methods are more "equal" than others. Don't think of PEX as a commodity item. There is a difference.

John, happy thanksgiving...

John_162

as Dan said the ASTM scientific testing shows them all the same. opinion make different. BTW if PexA is better why isn't it chlorine rated (NSF) for recirc lines