My $300 Solar Water Heater system for parents

[CmeBREW]

Hi Willib,

I think the idea is to have the layer of Silicone super thin so it makes a good solid thermal seal to the Pex.  Mine was messy and no doubt had bigger gaps which forced me to use thicker Silicone which I'm sure costs me some efficiency.

But it works quite good I think for a small 18SF collector.  

I realize now how easy it would have been to do TWO parallel lines instead of just one-- and I could have got 10 Runs inside the collector instead of only 6 runs--and it would self-drain just the same.

Also, thicker aluminum would've been even better as Gary had said-- but I couldn't find any for a reasonable price.

I'm not sure about that stuff you mentioned. Sounds like it would cost a lot.

Rather than spending a lot on special 'Thermal seal' stuff, I would rather just spend the extra on copper tubing and the thicker aluminum.

Thanks!    

[MattM]

PEX is supposed to deteriorate in direct sunlight pretty quickly.  How is your holding up after the first few months?

[CmeBREW]

Hi MattM,

The Pex looks fine to me so far.  The black paint over the PEX "ends"  is still sticking good so It will probably be fine for years.

Of course, the majority of PEX is covered with the aluminum absorber strips. And if one wanted to, you could always cover the "U-turn" PEX ends with a 10" wide piece of aluminum flashing to completely block UV from ALL the PEX.

Thats another reason I wish I had made a bigger 4x8' collector out of those Polycarb panels instead of tempered glass.  The Polycarb panels have 100% UV protection they claim, and less heat loss than glass. (single pane)

For my other projects I got the Polycarb panels from Lowes for just $20 ea.

They are called Tuftex.

http://tuftexpanel.com/

They certainly are tuff because I had them laying in my living room floor for weeks, and kept accidently stepping on them in the dark numerous times! Left no mark at all.

-Stores stock very few of these I found out.  So I'm going to get some more panels NOW for future projects, before the world ends in a few weeks...

http://online.wsj.com/article/SB10001424052748703574604574500580285679074.html

-Thanks.

[MattM]

You're coming up on the 8th month mark of operaton. How's the project going?

[CmeBREW]

Hi MattM,  

Sorry, just saw your comment. This project has went pretty well I think for the small investment.

I wound up shutting down the system (and draining the tank) for the two worst months of winter because I realized there just is not enough sun here in Ohio to do any good with this small collector. There was only 2 full days of sun in January! Rest of the time was no sun and gloomy.

But in March I re-filled the tank and have everything running again. There were no problems. Just took a few seconds to re-prime. I only filled the tank with 45 gallons this time so that the temp will go higher in the tank, hopefully like upto 120F-130F max.  I just thought it might be more efficient this way.

It has been used quite a lot now in this month of March. Looking forward to April and the summer!

-Thanks.