Solar Pool Heater DIY Solar powered by Stormspoons.com
This is a pretty simple project. Make a box, insulate the box, paint the box and add your tubing. Hook up a solar pump and heat your pool.
Let me break it down into how I did it.
3 2x4x8 pt board
1 1/4 4x8 pt plywood
1 construction adhesive tube (to attach insulation to the pressure treated box)
1 silicon tube (seals holes)
deck screws (variety of sizes)
1 sheet foil covered insulation ( I am pretty sure its polyisocyanurate but double check at the store) that is able to be spray painted
1 roll black aluminum door screen
2 12' long aluminum soffit pieces
2-3 cans black high temp spray paint
scrap or 1x2 pine moldings to attach the screen to the box.
1/2'' x 100 feet drip tubing (https://www.amazon.com/gp/product/B000WU5GGQ/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1)
!!!!!!!!!!!!!!Found out the hard way this is not to be used!!!!!!!!!!!!!!!Due to the high temps in the box this tube if water is not running through it it will melt! see pictures below. I went to find the next best tubing and realized we had an old 100' garden hose. Cut that and drilled a bigger hole and it works perfect. Even better then the tubing because the hose is soft.
1 solar pump and panel (https://www.amazon.com/gp/product/B073J1SL2Y/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1)
1/2'' tubing clamp
1 double wall greenhouse panel
aluminum tape ( to seal the ends of the green house panel
1. Using 2x6 x 8 (3) pt boards I cut one of the boards in half and screwed it to the other two. Making a rectangular box.
2. Added a sheet of 1/4 4x8 pt plywood (do not use OSB it will rot and flake off, I know this from experience).
3. Add insulation board. I used a foil coveredd foam that was about 1'' thick (polyisocyanurate). The foil gave me a surface to attach it to the box (construction adhesive)I insulated the bottom and sides. Then using high temp paint painted the entire inside black. (Check at the store for which insulation will not be eaten by the spray paint. One will be fine the other will be dissolved.)
3. In the pictures below you will see that there is black screen door screen and black soffit in the box. My box that I made was recycled from a previous home heating experiment. It worked great, but we did not like the insulation smell coming from the box. The screen and soffit are there to add heat sinks in the box, they also add a great place to put the hose on. I would still use them as we are getting great temps out of the solar heater. I attached the screen using 1x2 pieces of pine that you can get in the molding section of a big box store. I screwed them through the insulation into the box. ( The pine was pre-painted), then I cut two sheets of 12' long house soffit. Its aluminum (brown) but I hit it with the black paint too. Then using tin snips cut to size and screwed them into the box.
4. Next I drilled two 5/8 holes through one side of the box. I fed the cut ends of the tubing through the holes each piece was about 5' long hanging out of the box. (This will depend on how far away your panel is from your pool.)
5. I attempted a few things at this step. My frustration should save you a lot of time. I thought I wanted the panel/box at an angle when it was all done. SO I tried laying the tubing out in neat rows. Did NOT WORK, due to the tubes kinking. I tried spacer, tried making spacers tried using screws and wiring them in place.... then tried to set them up in loops, worked when flat but when I went to set it up at an angle it would not work as the draft is too high for the pump. Which then caused me to have to lay the box down (it is not light please use two people to move it) flat and then the pump worked. So to avoid two hours of frustration lay the box flat. It will still work I wanted it angled to get more solar gain but I am very happy with the temperatures we are getting.
5a. What worked was laying the box flat using a 5/8 auger drill bit to drill two holes and then to lay the pipe in there in loops to avoid kinking. I drilled from the inside of the box out to make sure the tube would make it past any screen or soffit. I used picture hanging wire to hold the loops together if they were kinking. I then hooked up the pump and double checked it all worked. It is OK to have the loops overlap. I am Very glad I double checked it because. I found a hole in the tube where a screw punched a hole it would have dripped and rotted the box.
5b. I did not go over base material because it will depend on where you place it. I used scrap 4x4 and 2x4's to make a base that hooked to my fence. This tripod design along with the fence let me make a really sturdy base. I will tarp it in the winter but will not move it.
5c. Put the box on the base. Get it where you want it because you do not want to disturb the tube. It kinks easily. Use a second person you do not want it falling into your pool or on you its heavy.
6. Check for leaks....I had a screw poke a hole in the tube. This is thin wall drip tubing and easy to do. I had to pull out about 5' of hose and cut it off otherwise it would have dripped in the box and rotted it.
7. Double check for leaks. Once your ready to add the top greenhouse panel first clean it inside and out.
8. Then using the aluminum tape tear a long enough piece of tape and go over the top and side edges to seal the greenhouse panel.
9. Then using screws attach the greenhouse panel to the box. DO NOT SCREW THROUGH THE TUBE. You have to watch in two spots for this (the holes you drilled) also double check that the tubing in the box is laying flat and not going to get pinched by the panel or by a stray screw. Screw straight down not at an angle.
10. Silicon the edges of the panel and where the tube comes in and out of the box. (Mice will love to live here in the winter. Seal them out!!! In the summer if its not sealed wasps will love it seal them out!
11. Hook the pump to the tube ( I would recommend a clamp from your pool company so you do not rip your liner. These clamps are normally plastic coated.)
12. Check the outflow pipe to make sure its smooth and will not rip your liner.
13. Attach the pump to the solar panel. This will allow it to run all day and turn off at night. If you run this at night you will cool your pool.
Does it work? YES!! After a few days of running this heater we are at higher pool water temps then we had all of last year. A similar project that I saw would raise a 28' pool by a 1/2 degree a day, our is 18' round and its more noticeable. Yes we use a solar cover to keep the heat at night.
Total cost for us was low, we had the wood from a previous project, same with the greenhouse panel. I had to buy one additional soffit, 1 can spray paint, the pump, the tube, and tube clamp. My favorite part is that it is set it and forget it. I do not have to turn it off every night. I am using free power from the sun, and I did not have to re-plum my filter and pump. The box is sturdy enough to be left out over winter and will last multiple seasons.
Feel free to use this. All I ask is that you keep the links back to my blog and website.
www.stormspoons.com I hand carve spoons and turn bowls on a spring pole lathe all from storm damaged wood. When not carving or turning I have other "Projects" :) If you would like to support us please buy a spoon :)