Radiant Tubing leak - how to repair?

itscoldoutside

Found a pinhole leak in my system which was installed in the late 80s. Uses a pair of web connected rubber tubes shown in this picture.



What is the right way to splice this tubing? After 30 years how much more life can I expect from this tubing? It is still pliable.

Zman

That's a new one for me. What part of the world are you in? Are there any markings on the tubing?
I suppose you could carefully cut the web out and use a barbed coupling and hose clamp.
Ill be curious to see if anyone recognizes that one...

Dan Foley

Solaroll

itscoldoutside

Zman said:

What part of the world are you in? Are there any markings on the tubing?

Located in the Pacific Northwest region of the U.S. I don't see any markings. The tubing is located in a crawlspace and stapled to the bottom of the subfloor.

Zman

https://forum.heatinghelp.com/discussion/81340/sola-roll-radiant-rubber-tubing-scale-buildup

itscoldoutside

Zman said:

https://forum.heatinghelp.com/discussion/81340/sola-roll-radiant-rubber-tubing-scale-buildup

Thanks for the link but it doesn't sound like a match for the tubing I have. What am I missing?

hot_rod

Sure looks like RadiantRoll, AKA SolaRoll from BioEnergy in NY, dates back to the 1980's.

Originaly designed for freeze proof solar collector construction.

Barbed automotive 5/16" couplers with nylon squeeze clamps works to splice or repair it.

If it rips easily with a fingernail, you're done. It was a straight EPDM and has a life expectancy. Exposed to light it seemed to break down in those areas first.

itscoldoutside

hot_rod said:

Barbed automotive 5/16" couplers with nylon squeeze clamps works to splice or repair it.

If it rips easily with a fingernail, you're done. It was a straight EPDM and has a life expectancy. Exposed to light it seemed to break down in those areas first.

Thank you. Unfortunately I haven't been able to find detailed spec information about this stuff anywhere on the net. The good news is that it was installed in a very dark crawlspace so it hasn't been exposed to any light. I am concerned that this pinhole leak may be an early symptom of the tubing hitting its end of life, but the tubing feels strong so maybe it was just a random event.

I'm measuring the ID at 1/4". Should I try a 1/4" barb first or is it standard to upsize by one to stretch the tube for a tighter fit?
What material do you recommend for the couplers?

hot_rod

Correct you are, it is 1/4" ID. These are plain vacuum line couplers from auto supply shops. Use a smooth clamp, not a stainless hose clamp they will cut the tube.

Hard to predict how many leaks, could be one or 50 .
There are still a handful of those systems operating in my area.

They do have a habit of sludging the system also, as it is a non barrier tube. It's not unusual to find some of the loops plugged solid with gunk.

I modified this air chuck to pressure test and flush the loops, but you need to cut them free from that funky manifold to test loop by loop.

This is the tube that spawned the Heatway TwinTran dual hose for a bit of trivia. Same concrete truck used in both ads I think

itscoldoutside

Thanks for including the info on this old style of tubing. Very interesting to see how they used it. Much different than my installation which is just tacked to the subfloor.

hot_rod said:

Correct you are, it is 1/4" ID. These are plain vacuum line couplers from auto supply shops.

For radiant heat systems is there a preference between nylon and brass for the barbed connectors?

hot_rod

Yes it was used as staple up also, it's just a tube at the end of the day

I prefer the nylon couplers. The machined brass tend to have sharp edges that could cut into the soft tube. Plus they are less $$

If you prefer brass, welding suppliers have that size for Oxy/ act
hose couplers. They have more of a rolled serration.

Also note, they claim in the brochure that it is a 3/16 tube.

Maybe take a sample when you shop for fittings, don't stretch it more then you need to on an over-sized fitting.

itscoldoutside

hot_rod said:

Yes it was used as staple up also, it's just a tube at the end of the day

After taking a closer look I found that mine was stapled to the subfloor. I'll need to find a away to reattached the section I pulled down to work on the leak. With the tight work space I'm not sure I can restaple without piercing the tube.

hot_rod

The staple up systems I removed were attached with construction adhesive! A clamp around it every so often.

I've also seen it glued on slabs and poured over.

Get some plastic plumbers tape and straddle the entire tube, nail or screw both sides.

itscoldoutside

hot_rod said:

Get some plastic plumbers tape and straddle the entire tube, nail or screw both sides.

That is exactly what I need! Thanks.

I'm on the fence on what do you with this system. I'm leaning towards pulling it out at some point but would like to use it for a few more years. Is it OK to run the system without antifreeze added if I'm not worried about the tubing freezing because we have additional heat sources?

HomerJSmith

If you want to use brass fittings, you might want to try Sharkbite Pex B fittings that you can find at Home Depot or Lowes.

Brass fittings have a smaller wall than plastic vacuum barbed fittings, so a bigger pass thru hole.

JUGHNE

You should be so glad that the leak wasn't buried in concrete!

nosirra1Arrison

Just as a point of reference...I just replaced a BioEnergy SolaRoll staple up radiant system installed in the mid 80s. It worked great. The EDPM tubing was still in great shape. The issue that killed my system was that the ph/water chemistry went bad and I ended up with pinholes in the copper piping that acted as an extended reverse return backbone manifold. Completely my fault. I had been monitoring it and missed a scheduled water quality check. The secret to my systems success probably was from no UV exposure and an incredibly detailed staple job that kept every inch of the tubing firmly against the subfloor as well as several water treatments over the years (35 years!).
My new pex with plates is much nicer, but I can’t fault the old school cave man system that served me well.
There is an article online of a Mother Earth News review of the SolaRoll product.

https://motherearthnews.com/renewable-energy/solar-heater-zmaz80mjzraw

hot_rod

nosirra1Arrison said:

Just as a point of reference...I just replaced a BioEnergy SolaRoll staple up radiant system installed in the mid 80s. It worked great. The EDPM tubing was still in great shape. The issue that killed my system was that the ph/water chemistry went bad and I ended up with pinholes in the copper piping that acted as an extended reverse return backbone manifold. Completely my fault. I had been monitoring it and missed a scheduled water quality check. The secret to my systems success probably was from no UV exposure and an incredibly detailed staple job that kept every inch of the tubing firmly against the subfloor as well as several water treatments over the years (35 years!).
My new pex with plates is much nicer, but I can’t fault the old school cave man system that served me well.
There is an article online of a Mother Earth News review of the SolaRoll product.

https://motherearthnews.com/renewable-energy/solar-heater-zmaz80mjzraw

I just threw out a 100' roll of RadiantRoll a week ago, getting ready to move, and I'm thinning out the herd.
I think you are right that fluid quality was key, dealing with O2 ingress in non barrier. A chemical romance can help that.

The original Heatway TwinTran was an attempt at an upgrade, heavier version of the SolarRoll. I still have a new roll of that kicking around

It's interesting how some of the non barrier tube works for years without serious component failure, other systems started failing within a year, pin holes in expansion tanks was usually the first symptom.
Copper pin holes are often caused by low ph.
Good reality check