I have 1200 sq/ft of infloor tubing ( hepex 1/2" O2 barrier) in my shop. 150' of 1.25" thermopex will supply the shop from a tarm in the attached house garage. A plate exchanger will be at the boiler or somewhere in the basement prior to where the thermopex will transit to the shop. Glycol will be in the shop loop. The probem is I also ran a set of 1" dura pex in the shop ceiling to another room in the shop. I just realized that Dura pex is not O2 barrier. I had the lines spray foamed in place. The lines are run for a possible water to air exchanger in the future room. I dont want to add another exchanger/pump. Does anyone have any comments on the proper plumbing (exchanger location, pumps,pump size for transit,pump location) for this scenario? Should I just forget about the non barrier or redo it with O2 barrier?
O2 barrier problem
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If the loop in question is not on the boiler side of the heat exchanger, you can use a bronze or stainless pump and not worry about it.
Or you can add some corrosion inhibitor to the loop and use an iron pump.
Or you can add some corrosion inhibitor to the loop and use an iron pump.
everything on the glycol side of the HX would need to be non-ferrous, if that is where the non barrier tube will connect. Including all the fittings, pump bodies, expansion tank, etc.
The lack of barrier on the tube will cause the O2 scavenger in the glycol package to be depleted. How quickly that can happen will depend on how hot you run the system. O2 ingress is much higher at higher operating temperatures.
Another option is to keep an eye on the glycol ph and add an inhibitor boost shot every few years.
hr
The lack of barrier on the tube will cause the O2 scavenger in the glycol package to be depleted. How quickly that can happen will depend on how hot you run the system. O2 ingress is much higher at higher operating temperatures.
Another option is to keep an eye on the glycol ph and add an inhibitor boost shot every few years.
hr
Sounds like I really screwed up. Can I slide a 3/4" line through a 1" line and use a different type heater in that room (cast iron rad,fin tube) or will it not fit through? Any other options?
You do have the option of an additional HX, if needed, along with its own circ and exp tank, for the ceiling future water/air system, and put glycol in that loop as well; essentially plumbed like the in-floor pex loop.
If I slid the 3/4" line through the one inch would I be able to get enough gpm's through that line that is about 25' from the manifold to run a low temp radiant device? Or will I need more flow than that. The room is very well insulated and has the infloor under it(bar room). I am planing on keeping the whole shop about 50 degrees,but wanted the ability to make the 13'x 18' room slightly warmer for watching Brett Farve throw touchdown passes. Will the 3/4" line give me that little extra im looking for? The entire area shop and baroom are one zone so if I could use the same pump and come of the manifold it would be the easiest and cheapest.
A 3/4 line normally is good for 4 gpm, which is 40,000 BTU's at delta-T=20, and I think low temp radiant normally is delta-T=10, or 20,000 BTU's. Calculate your pump head based on distance and equivalent length for fittings and see what circulator you might get to meet your needs.
Thanks Jebatty,but what I am looking to find out is if this 3/4 line was plugged directly into the manifold with the infloor zone can I just let the pump thats already running push water up the 10' wall through the 3/4 line for 15' over to the next room and back down to the low temp appliance. That way whenever the infloor is running, the water will also be flowing through the low temp appliance. Is that possible?
A sketch of the plumbing plan would be helpful. Otherwise, the answer is yes, no, maybe, to achieve an effective result.
I wish there was a way to figure the resistance of the total 35' of 3/4" line compared to the much longer length of each loop of 1/2" pex loops. Pictures and schematics are not yet in my computer abilities.
It's possible to probably calculate most if not all info you want. Talk to whomever designed and/or installed your system. That contractor should be able to provide you with all necessary information, as that information would have to be available to do an appropriate install.
How many 1/2" loops do you have? What is your target flow rate through each 1/2" loop? How long are they and are they all the same length? How long is the plumbing, what size, fittings, etc. on the loop between the heat exchanger and the manifolds for the 1/2"? What heat exchanger are you using for the 1/2"? What does the data sheet show for pressure drop at the target flow rate?
Your 35' of 3/4", are there any fittings (90's, 45's, etc.), and if so, how many? What is your target flow through the 3/4" loop? What heat exchanger are you using for the 3/4"? What does the data sheet show for pressure drop at the target flow rate?
With this info, at least an approximation of pump head may be calculated which will help in circulator selection.
How many 1/2" loops do you have? What is your target flow rate through each 1/2" loop? How long are they and are they all the same length? How long is the plumbing, what size, fittings, etc. on the loop between the heat exchanger and the manifolds for the 1/2"? What heat exchanger are you using for the 1/2"? What does the data sheet show for pressure drop at the target flow rate?
Your 35' of 3/4", are there any fittings (90's, 45's, etc.), and if so, how many? What is your target flow through the 3/4" loop? What heat exchanger are you using for the 3/4"? What does the data sheet show for pressure drop at the target flow rate?
With this info, at least an approximation of pump head may be calculated which will help in circulator selection.
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