No oxygen barrier help

rich_6

think you are right in that the o2 is the evel here. heat excg. are the way to go.

eddie grierson_3

No oxygen barrier help

Went on a estimate for a A/C replacement, When I arrived I asked the customer what type of heat he had, he informed me that he had radiant floor heat. So naturally I was wanting to leave the attic and head for the basement. On the way down I asked who installed it, he infomed me that he did it himself because he couldn't find any one to do it. Upon arriving in the basement I see a Phase III IDWH disconnected and replaced by an electric. I asked what happened, he said that was the second one in 8 years and he had given up. So I asked if I could see his slab tubing, then he showed me something I had never seen before. It was made by a company called Bio Energy; it was black rubber type tubing that looked like 1/4 inch, however the supply and return are connected by rubber and split at the manifolds.(solid loop) I informed him that I thought his Phase III problem was due to oxygen entering the system through the tubing. I also informed him that this was going to due the same thing to his cast iron boiler. This tubing is very restrictive I assume because he has large Grundfus circs piped in series for several manifolds. He also has 2 Utica 200,000 BTU boilers and only one is being used. The one has never been started. I told him about a Tekmar controller. All the floor heat is in slabs and has manually adjusted mixing valves. I was hoping you guys could give me some suggestions on what to due to save this system if it is possible. I don't think he is going to want to pull out the boilers and go with water heaters. So know I'am thinking plate exchangers or? Thanks for any help in advance.

Eddie G.

Tom Meyer

Heat exchanger

A heat exchanger seems like the easier and least expensive way to deal with any oxygen permeation issues in the embedded tubing. (This is assuming the tubing doesn't meet German DIN Standard 4726.) It would be worth checking with the manufacturer first. The heat exchanger would have to be located where everything on the primary side meets the 4726 standard. There is no point in installing a heat exchanger unless you can isolate the non-barrier from the barrier tubing. That being done, make certain all fittings in the secondary loop are non-ferrous.

Next problem is the second boiler. There are plenty of control packs out there which can switch the boilers automatically to ensure equal wear and use. Double check the manifold arrangement to make sure the boilers are "equal" in the system and there are no nasty surprises.

Senior Designer/Trainer
Precision Hydronics Corporation
www.precisionhydronics.com

hot_rod

Bio Energy solar roll

non barrier EPDM. Yeah, they have a habit of destroying boilers and pumps. Really best to isolate the tube from the boiler as others describe.

However, I would highly recommend you test each manifold and loop. It's not uncommon to see them sludged up to the point of no- flow. I have had some that I couldn't clear even with 100 psi water/ air pressure.

Make sure you are clear with the owners regarding repairs to this vintage "stuff" I'm not sure what the life expectency of that tube is. I'll bet that is 15 year plus system.

If you do tackle this, run the temperatures as low as possible to minimize the O2 permeation.

By the time you isolate and test all the loops, and use all brass or stainless components to seperate the system, these tend to be an expensive "salvage job". One that you really can't warranty!

Sounds like a heck of a system with that much boiler power! Make sure you don't has short cycling issues. That too will take out a boiler in a short period of time if they short cycle and condense most of their lives

Approch with caution!

hot rod

Tom Meyer

Only 100psi?

Hot rod: There was more than that hot air pressure coming out of the room at The Gathering!!!

I agree. Retros of this nature are dicey at best. Take your time, do it right and let the owners know it's a CPR job at best.

Senior Designer/Trainer
Precision Hydronics Corporation
www.precisionhydronics.com

eddie grierson_3

Procede with caution!

I agree, I have not done a load on the house yet. But I'll bet with just one of those 200,000 btu boilers is to large. I would like to use a buffer tank to help with the short cycling of the boiler or boilers. I have used a few large exchangers on pool heaters, I am thinking I am going to need a high capacity for this one. Do you guys know of a tank that I could use that would hold up to the oxygen? In other words boiler heats tank and tank feeds loops. I have used electric heaters for buffers but I am thinking of something like the ergomax. I don't even know if he wants to due anything yet, however when I told him he was going to lose those boilers like he lost those Phase III's, I got him thinking. My other concern is how long is that tubing going to hold up? He has no other source for heat. I'll diffently add strainers to the system. His system is in need of outdoor reset also. Thanks for the help guys.

Eddie G.

kevin

you could...

use a Superstor Ultra for the buffer and the Hx. All stainless. kpc

eddie grierson_3

Another ?

I have never used a Superstor before. Has anybody used these on systems without oxygen barrier? Will the manufacturer warranty them in this application? Anybody know where I can get more info? (website) Also anybody know where I can get one in the D.C. area? Thanks for the help guys.

Eddie G.

kevin

web site...

htproducts.com. They make two types. The Ultra and the Contender.The contender is not what you want , its all steel.T hey should give you a list of suppliers. kpc