5/8 tubing on 6" centers

yotakrawler

Hey everyone what is the best way to practically lay out 5/8 tubing on 6" centers.

Web says max radius is 6" for 5/8. Do I just let the 180 turns flair out?

Layout and heat load done by Rehau. 

Tubing is Uponor hePEX and will be attached to 6" wire mesh in 4" concrete.

hot_rod

Yes, you will have to “light bulb” the ends of the loops to get a tight spacing like that
why .5/8? Just to get long loop lengths?

mattmia2

why not interleave 2 tubes at 12"?

yotakrawler

Thanks that is a good idea. I am having a hard time picturing how that would work in a room that is a single zone and a single loop. Would the tube cross over itself? If they do cross over, what are your thoughts on the chair height for my wire mesh? Right now I am planning for 2 inch which give me 1.25 inch of concrete above the tubing. If have to stack the tube that only leaves about. 5 inches. I could get 1.5 inch chairs.

yotakrawler

hot_rod said:

Yes, you will have to “light bulb” the ends of the loops to get a tight spacing like that
why .5/8? Just to get long loop lengths?

Yeah, pushing 400ft in some places.

hot_rod

No harm in "over tubing" I'd consider two 200 '1/2" loops instead of a 350' 5/8".
More tube= lower SWT options, faster recovery, more even surface temperature.

mattmia2

I was thinking some sort of staple up. I will defer to others on how to handle crossing over in concrete. 2 parallel loops would reduce your loop length and might get you a smaller tubing size(although it would use a bit more tubing overall)

yotakrawler

Unfortunately at this point I have materials in hand and will probably have to make this configuration work. Any thoughts on what would be better "light bulb" or crossing over?

hot_rod said:

No harm in "over tubing" I'd consider two 200 '1/2" loops instead of a 350' 5/8". More tube= lower SWT options, faster recovery, more even surface temperature.

mattmia2 said:

I was thinking some sort of staple up. I will defer to others on how to handle crossing over in concrete. 2 parallel loops would reduce your loop length and might get you a smaller tubing size(although it would use a bit more tubing overall)

GGross

If you know anyone in your area that might have a pexgun wire tie tool to lend you they are super nice for tieing down to wire mesh.

I think I would "light bulb" personally. Normally I would have used 1/2" tube 9" on center, but more tubing is generally better, and I can't fault you for trying to do something better than average

hot_rod

There are other tube layouts some of these would only have one "light bulb" :)r

TAG

I would just go around the room ... that's how I did a big sunroom w/ lots of windows. In my case I did two loops that sit inside inside one other -- but one loop is just as easy. In a big space I like the loop around vs up down/ back forth.

yotakrawler

Thanks for the feedback everyone. I am attempting to do radiant cooling and that is the reason for the 6"spacing and the 5/8 tubing. My understanding is that cooling needs higher flow rates to maintain a lower delta T and the larger tubing keeps the pump sizes in check.