Don't Get Involved???

Rich Kontny_3

  My wholesaler who pushes Triangle Tube Products suggests that I don't touch a 5 year old house where they put in 1/2" pex tubing in there basement and garage slabs that does not have. an oxygen barrier. He says it is virtually impossible to get the temps out of standard tubing ???

   I am aware of the rust issues with ferrous components but I was unaware of any distribution issues with the non barrier pipe.  Any red flags that I am missing? I can use all brass and copper components to avoid the rust issues but would have to anti-freeze the two garage zones.

  Thanks for any advice in advance as I have not run into this situation before.

Rich Kontny

Mark Eatherton

Somethings fishy....

Let see, I have around 300,000 square feet of radiant floor projects, ALL of which use 1/2" HePEX and I have had no issues. At an average of 9" on center, that is 450,000 linear feet of 1/2" PEX. That's 85 miles worth of pipe, not including all the PEX distribution mains and snowmelt systems, and that is just me. The ONLY physical difference between HePEX and AquaPEX is the EVOH oxygen barrier.



I think someone screwed up and they are trying to cover their tracks, and are afraid that if you get involved, the truth will come out and they will look real bad...



But that's just my opinion :-)



I say go for it. Be the Knight in shining armor.



ME

icesailor

Water PEX/ HePEX

ME,

I don't dispute what you say. If there are problems, so be it.

My question though, I thought you were supposed to use HePEX on heating systems and Water PEX for domestic water. And not mix the two.

Where I work, there is a builder that started putting in GeoThermal and all kinds of other exotic heating systems. He is not a Plumber or a heater. He is a nail banger. He and his minions have been buying their equipment from an Internet provider of heating supplies and installing trhem in their "Green Buildings". They sold him a load of water PEX for the heat. They used all iron fittings and iron circulators. The system water is like coffee only thicker.

Am I mistaken that you aren't supposed to use water PEX in heating systems? 

Mark Eatherton

Nothing in the code prohibits its use in heating systems, but...

Chris,



I am not a big fan of using non O2 barrier tubing in anything but potable water applications, but the cost per foot looks attractive to some people who can't do the math and figure out how much more it is going to cost to do it right.



The RPA has three prescriptive methods for using non ox barrier tubing with ferrous components.



1. Mechanical isolation (flat plate heat exchanger with non ferrous components on the heating side, and ferrous components on the source side).



2. All non ferrou$ component$ throughout the $y$tem (EX$PEN$IVE)...



3. Regularly maintained chemical treatment to maintain a perfect pH for the components in the system.



Item 3 never gets followed up on, and the system ends up like you are seeing, blood/mud red water and eventual failure due to oxygen.



Some people just don't get it...



I did a potable water/space heating system in my own house many years ago, just because I could. I hooked it up to my DHW system. It really did little more than knocking the chill off the floor. After a few years, I decided to take it out and install a REAL closed loop heating system with plates and HePEX. In the process of removal, while draining the 3/4" poly butylene tubing, a bluish green slime came out of the pipe, and I decided at that point that I would NEVER expose my customers, or myself to the potential illness that the open system presented. That was the first, only and last open system with non ox barrier tube I ever installed.



I am of the same thinking as you, but unfortunately, it does get installed, as you have seen, and we are left to "deal with it".



There ought to be a law against it, but we are fighting an uphill battle with ALL of the tubing manufacturers, who's primary goal is to sell tubing, with or without an oxygen barrier, and I guarantee you they have more pull and sway with the code officials than we do.



We see eye to eye :-)



ME

bob eck

non barrier tubing

you should be able to do this job. if there is enough pex tubing installed. use a heat exchanger to keep boiler water on one side and the radiant water on the other side where the tubing is non oxygen barrier.

CMadatMe

I Will

Would be more than happy to sell you a heat exchanger and non ferrus components to make this work properly. As long as there is the appropriate loops lengths, insulation and water temp would work like a charm. The tubing isn't effected and you could tell just by flushing the lines to see if you get any crap our of them. Only the ferrous products within the system are effected.