Now that I figured out how to best insulate under the slab, thanks to some great feedback for you all, what PEX tube is right for the radiant heat under slab. I’ve seen PEX A,B and C, by Zurn, Wirsbro, and Slant Fin to name a few. Any experience out there?
Madmax
Replies
Use an oxygen barrier type to reduce the risk of corrosion of the metallic parts of your system. Other than that, use the type which gives you the best combination of purchase price of the tubing and purchase price of the fittings and tooling. Yeah, each one will tell you that their crosslinking method is better than the other guy's, but frankly I doubt it matters.
Around here the choice was between Wirsbo and Kitec, and Wirsbo won hands down on cost. They're a firm with a long and reputable history and I have no worries about my choice. Through this forum I've managed to find a kind soul who will lend me his hand expander tool to work with their fittings, which makes a world of difference on my DIY job.
I'll second the Wirsbo¯
We just completed a 42 story hotel/condo & put in 65,000' of 1/2" wirsbo.
PEXa, b, or c would be appropriate. PEXa is a little tougher and more forgiving because that process results in a more complete crosslinking of the polyethylene molecules. PEXc is said to lie flatter because it's crosslinked as it's pulled flat through an electron beam. No matter which you use, be sure it has the oxygen barrier, and that if it might sit out in the sun for a time, that it has an appropriate UV barrier.
Andy
"Never try to teach a pig to sing. It wastes your time and annoys the pig." Robert A. Heinlein
"Get off your dead #### and on your dying feet." Mom
heat pex can be used for water supply but water suppy pex cannot be used for heat.
Mr. T.
There's a steering-wheel in me pants and it's driving me nuts!!!
Depends on the brand. Wirsbo hePex is not certified for potable water.
oh
Mr. T.
There's a steering-wheel in me pants and it's driving me nuts!!!
Wirsbo/Uponor hePEX is not listed and certified to NSF Standards 14 and 61 for use in potable water systems, it is in fact manufactured to the same standards and specifications as their Aquapex product, that being ASTM F876 & ASTM F877, with the exception of the addition EVOH oxygen diffusion barrier. Uponor hePEX is almost twice the cost of their AQUAPEX, so regardless of construction and ratings, only the foolish or deparate use heating PEX for potable applications.
Good point.
And to those who say I had some left over so it didn't cost aything, when you try and sell the house, a good house inspector might find it and kill the sale.
OOPS.
"And to those who say I had some left over so it didn't cost aything..."
Well, most of my customers for PEX products (I sell the Uponor and Rehau lines) are one or the other, that is, they either do the potable side or the heating side. Very few of my customers do both.
"...a good house inspector...." I've heard these exist, never actually seen one, though ;p.