Fixing up a free solar hot water panel

[thatguitarguy]

I took a look at your project page, and the tank that you are calling a "pressure" tank looks very much like my tank except mine is 80 gal. Mine is not a "pressure" tank, it's a secondary tank with a built in coil that runs from a boiler. You ought to inspect yours a little closer to see if you might have that coil already built in to your tank. It would be more efficient than wrapping that copper around the tank to transfer the heat.

Looks like it's working well! Are you still using water in your heating loop, or have you switched to the glycol yet?

[bennelson]

I can assure you that there is no hidden coil already in my tank.

But yes, you are correct that a coil INSIDE would be much more efficient.

That's basically the plan right now, is to cut the top off the tank so I can make my own coil to place inside the tank.

No I am not using glycol yet, as I am still just experimenting. Water works great, is cheap, and I have no problems with spilling it on the ground.

One thing I should do is completely fill the panel with water, and then drain it all back into a bucket to measure. That, plus a calculated amount of tubing should tell me exactly how much anti-freeze I will need to buy.

I did find a home improvement store that carries "Hydronic & Solar" antifreeze by the gallon and 5-gallon containers. It costs about $15 per gallon, but I really don't think I will need too much.

[bennelson]

Today, my solar hot water experimentation got a 55 gallon upgrade. I know a guy who works for a company that uses plenty of 55 gallon drums, and he had a few from work. I zipped over to his house on my lunch hour in the Electro-Metro and tossed the barrel into the hatchback. (There was actually enough room in the car for two!)



Back home, I cut the top off the barrel, and washed it out as best I could. (It still smells like artificial cherry flavoring…)

I then transplanted the copper coil pipe into the 55 gallon drum and filled it up with the garden hose. I bent the end of the copper tube to drain back into the 5 gallon bucket with the pump.



I figure that by heating a 55 gallon drum of water, I am getting a better estimate of what should happen in my 50 gallon steel tank when that is used as the final solar tank.

After a couple hours in the sun, the whole barrel was fairly warm (130 degrees) – not as hot as the the 15 gallon tub got, but still nice and warm.



I’ll report back in after the next full day of sun to let you know what kind of thermal heat I get from that.
________

[MetroMPG]

Nice experiment.

I laughed at your plastic 55 gallon drum washing story. Last one I got contained the orange food colouring used to tint cheese.

[bennelson]

Did some more work on the DIY Solar Hot Water system.
I cut the top off the steel tank and installed coiled up copper pipe inside, then hooked all that back up to the panel.

http://www.youtube.com/watch?v=0zuSpITCIRM

http://www.youtube.com/watch?v=s0Bkgj63OpE