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Entran III

John Ruhnke_2John Ruhnke_2 Posts: 665Member

Call up Dan Chiles of Watts Heatway. I don't have his number. I had a client with an old Heatway twintran system. We repiped it with a heatexchanger. The tubes were clogged with rust from the oxygen corrosion of the boiler but there was no signs of leakage anywhere. The system was 15 years old or so. WE unclogged the tubes with an air compressor. Dan sent me some manifolds and clamps to do the job. Its been a few years since the project and the client has been happy so far with no problems. I don't have his number. I'm sure you could find watts heatway through google and they would get you in touch with him.


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  • Nick SimoffNick Simoff Posts: 1Member
    Entran III

    Hello, I'm Nick Simoff of Absolute Comfort Heating and Air conditioning in Colorado Springs. My question is: What do I use as a sealant, if anything, when re-making connections at the barbed fittings of Entran III? I have an existing system that requires a boiler change-out and must re-do several copper to Entran III connections. Heatway used to supply a two part "goop" that worked well. I have fittings and tension clamps but, no "goop". What was the the inner liner made of? I'm looking for something, like red silicone, that will seal but not react with the rubber.

    Thank you, Nick Simoff
  • hrhr Posts: 6,106Member
    Hard to find anyone that will

    answer those questions anymore :) I'd have to dig a little but different vintages of that tube used different "sealants"

    One product, BarbTite looked and smelled like regular rubber cement, to me :) SureTite was the 2 part epoxy stuff. I have some but way past the 30 day shelf life :)

    There were a bunch of different clamps produced over the years also. Different thickness of metal as well as different metric sizes for different styles of tube. The size should be stamped in the clamp.

    How is the tube holding up? Still soft and pliable? Any leaks around the connections? If you have the correct barb and clamp AND the pressure is 10- 15 psi, think I would just clean the barb real well and reuse the old clamp. You may not find new clamps anyways. I don't think the current Onix clamps will fit that tube.

    Use care when you cut off the old connection as not to score the brass barb with your knife.

    I'd go with a self tite or the constant torque style clamp if you can find new ones.

    hot rod

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  • DU423DU423 Posts: 1Member
    Entran Three Radiant Heat Tubing Help!


    I just found out that my Entran 3 has some sludge building up.  I don't think it is as bad as Entran 2 (which is nitrile rubber, 3 is EPDM).   However, does anyone know what i can do to combat this?

    Can I flush it out, or put in a stabilizer, can it be saved?  

  • kcoppkcopp Posts: 3,324Member
    start by....

    using plain water to purge.... then use a product called Rhomar. The 922 cleans the system up. It will need to run when hot so July is prob not the best time to do this. Then add the system stabilizer after you flush out all the yummies. 9100 I think.
  • High_DesertHigh_Desert Posts: 3Member
    entran 3 repair, please help

    I know this thread is old but it's very relevant to me at the moment.  I

    am a contractor renovating a bathroom and one of my guys hit a hydronic

    line in the slab made of entran 3.  I need to repair the line but

    cannot find any information about how this should be done correctly. 


    did the original couplings look like?  Any suppliers around that make

    anything that would work?  Anyone know the exact I.D. of Entran 3?  I

    know this tubing can be a little brittle and so I don't want to stretch

    it out too much with the wrong fitting.

    We have a piece of 3/8"

    copper in there now like a stint with some band clamps around it but

    this does not seem like a good long term fix.

    Any ideas?
  • kcoppkcopp Posts: 3,324Member

    E3 was orange and it did Entran 3 written on the side. The fittings are generally speaking the same as the Watts Onex that are around now....Barbed w/ tension clamps. The stuff is brittle so be VERY careful.
  • hot_rodhot_rod Posts: 11,252Member
    E 3

    was one version of the transitional hose between the Entran 2 and twinTran that had some "issues" E3 evolved into the current Onix.

    The 3/8 barbed coupling that fits Onix should work, but you would want to use the stainless style clamp if it is going to be buried.

    They had a stainless gear clamp with a spring washer to cold constant tension, called a TorqueTite 17-19mm size (2007). Over the years it was also called a SureClamp (2002), and SelfTite (1994)

    A hose clamp and barb 3/8 coupling from an auto parts would be one option. Don't over tighten the clamp or it could damage the soft jacket.

    The factory stainless clamps has a smooth inside, unlike a traditional gear/ hose clamp. The factory spliced tube had a heavy shrink tube over the splices.

    It would be a rare find to come across the exact clamp for that vintage tube, and the adhesive that was used. There were a number of different diameters of that tube as it evolved..
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • High_DesertHigh_Desert Posts: 3Member
    Thank you so much for this post!

    This was very helpful hot rod, thank you so much for such an informative post.  I have been amazed how difficult it has been to find information about this distribution system.  I know this tubing is delicate and didn't want to dig my hole any deeper by using the wrong fittings.  I will start the hunt for Onix fittings unless you have an online source you could recommend. 

    I have a follow up question for you (or anyone else with experience with Entran 3).  The fluid that came out of the loop had a very distinct odor.  It was like old dirty hose water and antifreeze.  I am guessing that this is probably a combination of age and possibly some sort of chemicals added to the water.  Does the water in the loop need any kind of chemicals to stabilize the rubber or minimize oxygen absorption?

    Different but related note: I recently bought a house that also has Entran 3 and the fluid was purged prior to the sale to winterize the home.  Before we fired up the heat we filled it up with water, should we have added something else?  The new boiler and circ pump are not brass.
  • hot_rodhot_rod Posts: 11,252Member

    is not the same hose as the E2 and twintran. The E3 version was on it's way to becoming the current Onix which now has an aluminum wrap and multiple layers to address O2 ingress.

    The concern was alway about the O2 ingress, or the amount of ingress. I suppose that is why different compounds, barriers etc were added or changed.

    I have not seen any E3 get hard and brittle like some of the E2 and twintran did, but...?

    Different opinions on leaving or flushing the fluid. If the system is flowing, heating properly, and not causing pumps and expansion tanks to corrode, I would leave it.

    The theory was flushing the smelly fluid might flush the plasticizers that are keeping the hose intact.

    In fact when the tube started to harden tests were done to try and add plasticizers and antioxidants back into it to

    Various chemical treatments were promoted with that tube including the Fernox SuperFloc cleaner, CP-3 corrosion proofer and Alphi 11 for glycol systems.

    Fernox products are showing up again in the hydronic market, hmmm?

    Did the system ever have glycol? Were treatments ever added? Check the fluid ph?

    The Germans developed a DIN standard back in the 80's when O2 was rearing it's head in plastic tube systems in Europe. HI (hydronics Institude) endorsed parts of that standard DIN 4726 including

    Use of only barrier tube

    Non ferrous components or isolation with a HX and non ferrous pumps, etc

    Ongoing anti-corrosive additive and fluid testing.

    I'd consider a chemical treatment to the system that has fresh water, Rhomar or Fernox and check it yearly with the proper test kit, need to keep the O2 in check or things could go downhill quickly. Higher temperature promote faster O2 ingress, run it low possible and on a reset control.

    The tubing has a lifetime warranty and the manufactures promoted it as "high-pressure high-temperature and very unlikely to deteriorate before the building is torn down"

    How's the building holding up :)
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • High_DesertHigh_Desert Posts: 3Member
    Again thanks hot rod

    Again a very knowledgable and helpful response. Very grateful for your taking the time to share your insight. I feel much more confident moving forward now.

    House is still standing ;)
  • kcoppkcopp Posts: 3,324Member
    If the system....

    had std glycol added to it is could make the entran more brittle and plug it. I had this happen one time and the entire staple up had to be removed. Rhomar products a re great. Be careful about adding top much of anything as it could make the system degrade. Flush w/ good quality water and add the inhibitor from Rhomar.

    Watts makes the Onix tubing so any supply house that carries their products can get the fittings. If you are in the NE FW webb has them.
  • hot_rodhot_rod Posts: 11,252Member
    the current splice kits

    will work on the 17- 19 mm tube, by the looks of it. This one is what I would use for in-slab repair. exposed splice could use the spring clamps.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • cliffcanfieldcliffcanfield Posts: 1Member
    i know these posts are older so i am asking for any recent updates or follow ups anyone my have regarding the heatway entran 3. i have a customer who needs a repair. please
  • hot_rodhot_rod Posts: 11,252Member
    Do you need connection parts?

    is the system operating and heating adequatly?

    What is the date code on the tube?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
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