Rubber? loop piping for radiant heating zones in mid 80s BC, Canada home - anybody?

[John M]

Finally I have something to post!

I have inspected a home in Whistler BC Canada, constructed approximately 1986. Home is architecturally designed with some above average fixtures/finishes for the day (pella windows, in floor radiant heating etc).

The home features two boilers connected in series (which seemed a bit odd) and appeared to have 7 zones (three floors).

The one thing that appeared unusual was the piping for the floor loops. There are copper manifolds supplied by copper piping, but the in-floor loops are what appears to be black rubber hosing approximately 3/8 inch diameter.

While I generally always recommend an follow-on evaluation by a radiant heating specialist, my usual guy hadn't heard of this type of piping when I described it.

Anybody know what it is? When/if it was approved? and most importantly any expected service life ranges? Home is now 25 years old.

I will try to attach a few pictures

20723

20724

[Steven Turetsky]

It's hard to tell in the pix if it's pex.

[Rod Butler]

No markings? It could be polybute based on the looks and the age.

Polybutylene pipe as I recall became brittle because of chlorine and there were massive failures and I think it was pulled from the market. I hope that is not what you have here even though the water change rate should have been minimal to nil because it is a closed loop system.

I love in floor radiant heat but the problem is that there are a lot of older systems installed that used the wrong materials or were not maintained properly and were abandoned in place.

If you are really concerned talk to an old plumber that can steadfastly identify the type of pipe and go from there.

[Jim Robinson]

I have seen it, and forget what it was called. It's not Pex. I believe it may have been made by Watts, and was EPDM material. My plumber knew of it, but I can't remember any specific problems associated with it.

[Joe Klampfer]

... I can't remember any specific problems associated with it.



I have seen it once before a number of years ago, also in a high-end home. When I researched it I found that it was still a non-oxygen barrier tubing and prone to all the same failures as non-oxygen barrier poly-b. This tubing is also prone to becoming brittle and cracking due to age and temperature cycles. Another concern is also UV degradation the pipe may have been exposed to while sitting in the suppliers compound, prior to being shipped to the installation site.

I'm surprised it went 25 years without failure (but then, even epdm gutters have a 25 year life expectancy). Did you notice any patched areas or signs or repair ? How old was the boiler ? The boiler's heat exchanger is prone to failure unless it is of a non-ferrous type, (or equipped with an isolation heat exchanger and properly configured mixing valve). It also looked like the tubing exited the slab without protective sleeving.

To sumerize... it's not good stuff for that application.

[John M]

Thanks for the replies to date.

To clarify/elaborate - Piping is NOT any of the usual radiant loop material I typically encounter (ie not PEX, not 'regular' polybutylene (grey), not the red/orange poly b, not Entran, not CPVC).

It feels soft to squeeze and the best comparible that I can think of would be the black rubber hose that carries radiator fluid to the expansion tank in a vehicle. Diameter is about 3/8" OD (smaller than usual hence more loops of the manifold).

I am trying to track down more info from local heating contractor and the boilers were apparently replaced five years ago (unknown if replacement was of original or replacement boilers). The best info I have from the dispatch is that the radiant heating technican indicated the black piping was 'not good' - it might not be bad, but no idea of expected service life.

In hindsite, I was perhaps a bit bold in squeezing/rubbing/tugging on the tubing - it would appear that it is simply stretched over a metal nipple off the manifold (no external clamp noted).

I will add another post when/if I figure it all out! Thanks for the assistance to date.

[H.G. Watson, Sr.]

That doesn't appear to be "in floor" heating, but "Under the floor" along with supply and return loops to the manifold.

Onix radiant tubing has been made by Watts for decades. Everything "opined" or "remembered" by J.Kl... is untrue about Onix.

And YES Onix has an 0xygen barrier - that's one of the functions of the aluminum shield layer within ! And yes, that's EDPM.

Unlike Pex, it retains its flexibility and feels pliable even when cold, and one of the reasons it is preferred for under floor heating especially in cold climates heating 1st floor over garage, basement, or crawl). Also unlike PEX, you don't have the UV concerns. Its also used for some snow melt systems. It has multiple layers including barriers. It is not the problem Joe claims it is, for none of the reasons he stated (in fact Onix is the opposite of just about everything he said), it is one of the more ideal products to be used in the situation you have pictured and described, AFTER the distribution manifold from the boilers. Onix can handle HIGHER water near steam temps (unlike most PEX).

If you search "radiant onix" (without the quotes) in whatever search engine you favor, you should come up with at least a dozen links to Watt's site and to old versions (such as on scribb) of older installation instructions, etc. Current documents (installation instructions, technical specifications, warranty, etc.) can be found on the Watts site.

Onix is NOT PB. There is no PB in Onix.

Here is the main page from WattsRadiant on Onix: Watts Radiant - Onix (http://www.wattsradiant.com/products/onix/)

Here is a link to the Fact Data Sheet for Onix (I've also attached the PDF): http://www.wattsradiant.com/literature/download/WR_Onix_ProductSheet_FDS-EN-20030701.pdf

And here is a link to the current warranty, Its 25 years btw, although they've added some more exclusions recently: http://www.wattsradiant.com/literature/download/WR_Onix_Warranty_HeatSnowMelt-EN-20100426.pdf I've also attached the PDF for the present warranty.

Like all such tubing systems, yes there are proprietary clamps, attachment methods, etc.

[H.G. Watson, Sr.]

I have seen it once before a number of years ago, also in a high-end home. When I researched it I found that it was still a non-oxygen barrier tubing and prone to all the same failures as non-oxygen barrier poly-b. This tubing is also prone to becoming brittle and cracking due to age and temperature cycles. Another concern is also UV degradation the pipe may have been exposed to while sitting in the suppliers compound, prior to being shipped to the installation site.

I'm surprised it went 25 years without failure (but then, even epdm gutters have a 25 year life expectancy). Did you notice any patched areas or signs or repair ? How old was the boiler ? The boiler's heat exchanger is prone to failure unless it is of a non-ferrous type, (or equipped with an isolation heat exchanger and properly configured mixing valve). It also looked like the tubing exited the slab without protective sleeving.

To sumerize... it's not good stuff for that application.

If you're referring to Onix (WattsRadiant) there's not one thing stated above that's true, in fact its completely opposite.

Onix has a proven track record from the early 80s, and the materials and similar applications go back to WWII.

[Joe Klampfer]

If you're referring to Onix (WattsRadiant) there's not one thing stated above that's true, in fact its completely opposite.


Let me start off by saying "good work" and good info HG (two posts prior). Still a little wordy but I learned something :)

The pipe I saw (probably 15 yrs ago) was also an epdm material but it was not ox-barrier, nor did it have the reinforced aramid cord. I don't recall the markings on the pipe, and spent the last 30 min searching around (unsuccessfully) for the sample piece I picked up from below a previous repair site in that crawlspace.

The results of the research I did back then was that it was not good. I have never seen it since.

[Glenn Duxbury]

Hi, ALL &

Thanks, John, for a good head-scratcher !

See you next week @ the BCIPI Seminar &

Best Regards


CHEERS !

[Charles Smith]

SMALL BLACK RUBBER TUBING

I have seen it a couple of times. Does not appear to have oxygen barrier in material.

Radiant Problems (http://www.radiantdesigninstitute.com/page80.html)

"This tubing comes as individual 3/8" tubes or with a group of tubes with a web between them. This material is ethylene-propylene-diamine or better known as E.P.D. or SoloRoll. It was developed for roof top solar collectors for heating swimming pools."

[Ralph Holden]

Looks like it might be Entran II made by Goodyear for Heatway. I never used it but read about it. I don't know for sure if they made it that small. The only piece I ever saw looked more like 1/2" iron pipe size rubber hose. Had a lot of problems in the early 90's and was pulled from the market after a bunch of lawsuits and settlements.

[Daniel Leung]

Entran II is a reddish-orange rubber tubing, usually stamped "Heatway".
From John's photos and description, these black colour tubing is a kind of soft rubber. I support Charles finding, it is EPD.
I first noted this kind of tubing in a 1996 built house in West Vancouver. No leaking or damage found at 9 years old (see first photo).
Recently I visited a friend's house built at 1990 in Vancouver, it has 3 leaks all from the cracked/aged tubing near the coupling at manifold since 2 years ago (see painted tubing in second photo).

[Joe Klampfer]

Entran II is a reddish-orange rubber tubing, usually stamped "Heatway".
From John's photos and description, these black colour tubing is a kind of soft rubber. I support Charles finding, it is EPD. ).


That looks like the stuff I was referring to, thanks Daniel

It's interesting to think that non-ox barrier poly-b, supplying a manifold full of this tubing was once considered state-of-the-art.

I first saw it in a very high-end home on the bluff of Crescent Beach (south of Vancouver).

[Jim Robinson]

I really hope we aren't having the same conversation about PEX 15 years from now. It seems great so far, but who knows.

[Tom Rees]

John, I ran into the same piping on my buddies house and am still trying to figure out what is, manufacturer etc. Link to original thread: http://www.inspectionnews.net/home_inspection/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/22806-radiant-heat.html

Notice the failure at connections to manifold. I have a piece of it sitting on my desk and after reading HG's post I went back and took another look at it, there is no oxygen barrier or metal sheathing. It appears to be epdm only with no other layers. I have a good friend who is a commercial mechanical contractor and he can't identify the manufacturer but he remembers there being some problems with it. If anyone knows more about this or is on a HVAC forum I would appreciate your help. Thanks!!

[Egbert Jager]

<started a new thread instead of continuing here>