Probably a crazy question on HW solar

[Dayton Johnson]

Is it possible to install HW solar panels to a pole mount? I realize the piping,fittings and flexability etc.issues but i'm presently looking at having a new roof installed and need to remove my panels. I have one of those old style Ginormous sattelite frames located too close to my house and have wondered about removing the dish and putting panels in place of. The direction arm still works too! Ever heard of this or is it even possible?
I guess one advantage would be one could keep the panels brushed off in light snow and with a few more add-ons, panels could be tilted out at dusk for protection.
All comments or ideas welcome.

[Dave Turpin]

I don't see why not. Use PEX lines to and from so that it can flex with the array movement. You will need to make a custom frame but the sattelite tower should be strong enough. Then you can automate it and make it a 2-axis tracker for the ultimate in efficiency.

[Paul Bailey]

PEX lines and solar hot water do NOT always mix and will surely be a problem if overtemp occurs with moderate pressure. Paul:oh:

[Dave Turpin]

PEX uses crimp connectors and is rated to 100 psi at 180F. Hydronic PEX is rated to 100psi at 220F and has an O2 membrane. Your picture shows polyethylene tubing, which is not designed for high temp. (PEX is cross-linked poly, similar in all but what is really important)

[Paul Bailey]

Dave:Re your Pex PEX uses crimp connectors No not all pex uses crimp connectors as you stated, there are thousands of systems that have removable connections and NO crimps.And not all radiant/heat systems use O2 barrier pipe as they probably should but it depends on the system. Yes the picture is PEX and yes a solar water system can and will melt it under certain circumstances....Why even risk using pex in solar application that will produce 300 plus degrees if stagnated?.. more to follow Paul

[Dave Turpin]

That may be so, but that picture is definately NOT PEX.

The opacity of the plastic is a dead giveaway. PE is semi-transparent, PEX is completely opaque. PEX also does not fail in the way it shows in the picture, even at high temps. It will split, not bulge and rupture. I did lots of destructive testing on pipes of various polymers back in MSE 420.

If you have a solar water system that is exceeding 180F at 100psi, there will be other problems. Like scalding yourself to death.

[Paul Bailey]

PE is semi-transparent, PEX is completely opaque. PEX also does not fail in the way it shows in the picture



Well Dave: I'll add some more pics from contractors that have installed PEX and failures have made them really look at what not to install next time, we are in a debate over PEX vs Pe , So the rules have changed for these guys . No Plastic anything Period....pex / Pe / Pex-Al-Pex / Pe-Al-Pe / and yes the pvc and cpvc's pipeing as well, None at all . Enjoy the Pex pics from 3 diff. solar installs. These are costly mistakes from veteran installers. more to follow with some better options..:idea:

[Dave Turpin]

Yeah, that's more like it. #1 was overpressure, #2 overtemp at high pressure. I don't know what happened in #3... Something acidic in the concrete?

I think we can both agree using PEX in a closed-loop system without pressure reliefs and a emergency heat sink is probably a bad idea. But I could say the same about copper.