I made this solar-powered swimming pool heater out of common materials anyone could get, with ordinary tools most average homeowners have (or can borrow from friends). A friend of mine named Ace gave me a sliding glass door that was going to be thrown out from a job site he was working on (he's a roofer, and the door had some minor cosmetic damages to the metal frame).
Step 1: Building the Collector Box
I decided to make it out of pressure treated 2�4s and 3/43 plywood - the glass had leaned against my studio for over a year and you can see weeds and the weather had them filthy (wow I need to pressure wash my siding):
Step 2: Sizing the Box
So the size of the collector box was dictated by the glass size (76″ x 46″). Here’s my little helper buddy Muggy (my 6 year old son) helping me lay out the copper fittings - he was a big help throughout the entire project :) . Also you can see part of my German Shepherd Hoppy - she was NOT a big help:
Step 3: Copper Flashing Backing Plate
I ordered a 102 x 203 roll of heavy copper flashing .0216 (standard heavy weight for larger craft work, roofing and range hoods etc.) from Storm Copper Components - they are great, lowest price I could find and when I unrolled it it was almost 63 longer than 102 :
Step 4: Manifold and Backing Plate
I cut it in half and laid the two sheets under the copper manifold I made from 1/23 copper tubing I got from Lowes (the total copper cost in this project was around $250.00):
Step 5: Soldering the Manifold to the Backing Plate
Then I had a hard time soldering the tubing to the flashing, the heat tended to make the flashing buckle - I screwed the tubing down tight to the flashing with metal strapping, and just did as much as I could - skipping spots when the gap got over 1/8 of an inch or so. Still I made contact with around 70% of the tubing I think:
Step 6: Building the Support Structure
I used my deck for part of the support, and sunk 2 4×4 posts for the other side. There is solid bedrock about 8 inches down there, so I dug big holes, used a rock hammer-drill to drill holes into the limestone at angles and put 1/2″ rebar in the bottom, which I then filled with 4 - 80lb. bags of premix concrete (we get some serious thunderstorms with strong winds):
Step 7: Calculating the Angle and Running the Supply Pipe
I mounted it at a 45Â° angle, which may seem strange (my latitude is 38.42444) but hereâ€™s my reasoning: According to this cool sun angle calculator, that is approximately the optimum angle for me during early April and late September between 10:00AM and 11:00AM, which is when I need the heating most - during the middle of summer the water sometimes gets too warm, so maybe Iâ€™ll be able to run the system at night and radiate some excess heat.
For the supply side, I tied into the pipe going from the filter to the jet, and used 3/4â€³ PVC which I buried in a shallow trench (There is a tee with a drain plug at the lowest point, for winterizing):
Step 8: Hooking the Supply Pipe Up to the Pool Pump
I thought I might need a valve between the jet and the output to the heater, but it wasnât needed - there is a lot of pressure going to the solar heater:
Step 9: Mounting the Box
I painted the interior flat black, and used weather stripping between the wood strips supporting the glass and the glass instead of silicone - itâs not airtight (there are several âweepholesâ drilled in the bottom for condensation). This way if I ever need to I can unscrew the trim and remove the glass easily:
Step 10: Intake Valve
I can turn it on or off with a simple valve:
Step 11: The Outflow Pipe
The outflow is copper tubing:
Step 12: Install the Glass and Trim
Here’s the finished heater with glass installed and trim (I’m going to treat the trim and support boards with the same color stain/water seal as the decking and the collector box when the weather forecast calls for a few days of sunny warm weather).
Here is a little data I’ve been able to collect:
It is flowing at 3 gallons per minute (180 gph), and at 10:30AM on a sunny day the pool temp is 58° (it was 54° this morning at 8:00AM). I filled a gallon jug with water from the outflow of the solar collector (20 seconds) and the temp was nearly 61° - so it looks like on a really hot sunny day I could hope for a 4° or 5° rise in outflow temp. I think the pool is around 10,000 gallons, but trying to figure the math of it makes my brain hurt (I’m a musician, not a mathematician dammit!) and I guess it really doesn’t matter - if it works and I get even a few more days of comfortable swimming per year, then I’ll chalk this up in the WIN column :)
BTW if you get a chance how about digging this? Digg this
andrefierens made it!