Solar Pool Heater and Diverter

Watch this video to see our solar pool heater design and learn some tips and tricks when building your own. We are in the second season of using this solar pool heater to heat our pool and have been very happy with the results thus far. The heater is made of 2X4 construction and 3/4" particle board for the box. The tubing is 500 feet of 1/2" irrigation tubing which was purchased for less than $20. Once I get the tubing back into place I plan to cover the entire box with a piece of glass, plastic, or some other transparent material that can hold some additional heat in around the tubing.
The diverter that I made here diverts some of the flow of pool water from the pool pump for both my solar heater and the wood burning heater. I let this run continuously through the solar heater when it is sunny. I will post a separate video on the exact temperatures once I get some figures put together but the heater helps keep the pool temperature around 80 degrees with less than 8 hours of sun light on the solar heater or pool. I also use a wood burning pool heater if we have a few days of rain or clouds to boost the temp back up.
The overall cost of this project with the irrigation tubing, fittings, pvc pipe for diverter, valves, and wood for the stand was about $80. I also used some stain that I already had to seal up the untreated wood a little bit as well. Compared to the cost of the solar heaters that you can purchase this project is a fraction of the cost with more surface area of tubing that can capture more heat energy.

Thanks for watching!!

[edinaldomanuel]

Great job mate...very simple and efficient. I'm working to setup a solar water heater for my grand son in Berrien Country, Michigan. So I order a Solar Water Heater Book, to help me to complete the job. As a HVACR and Plumber Tech, this is new to me, but with your simple project and others idea's, I think that I'm able to start and finished the job before the summer. Great video.

[mrmadame]

In fact, you want your water to go fast through the piping. You prefer to have a lot of water heated off just a little bit. It mean the system is more efficient because for every degree your water take, the heat transfer between the hot pipe and the water is slower until they are both at the same temperature and the heater is very unefficient. You are right, no need for any mecanism. For 500 feets, I would prefer to do 5 loop of 100 feet in parallel. Also, never ever close both side of the solar pannel. the pressure can get quite high inside the tubing. Good job and thank you for sharing your design.

[cindysmith]

I have an above ground pool display that is only 8' diameter, the smallest they sold to the public is 12'. My $12 100' foot roll of black poly is made on a 3'X3' square, and 200' could easily fit on a 4'X4' square. My box walls were made from 3-side aluminum channel beams from old discarded hot tub covers. Once the coil is in place another beam is wedged in to hold it flat, perfect fit. Big Box stores for plexi is an expensive route to go. I went to a plastics supplier in my area called Midland Plastics, and I got a 3'X3' piece for under $20. So aside from some barb fittings, the bypass valve, etc... my major expenses were $32. And with a solar cover to trap the heat in at night and timer to run the pump daytime only... VERY EFFECTIVE!!!

[logan]

I did the same idea 20 yrs ago, I used black heavy gage plastic roll to enclose it

[mudhound]

Fencing wire woven in and out the back and in around each hose would keep it located, it would be time consuming but very inexpensive. Plexi glass over the top might be worth looking into also to prevent any wind/breeze from acting as a cooling effect. Great videos! Cheers!

[EviLzLiKeNeO]

THANK YOU for pointing out that the more/less water intake has nothing to do with anything. It's been driving me nuts.

[BasicPoke]

That's really neat, man, thanks for the video.  I will have to argue that water flow rate does matter, although I have not done any testing on it.  The cooler the water is in your coils, the faster heat will be transferred to it, so this would point to a higher flow rate being more optimal.

[chrisdaniel]

Please consider putting a sheet of tempered glass over the box, you will notice a dramatic difference in the efficiency of the heater and a temperature increase in the water exiting the unit. Also consider getting some polyisocyanurate insulation at the home center, it has the highest R value and max temp of 250F, place the insulation under the coils and around the walls, insulation plus the glass cover will make a huge difference.

[OakesProject]

Excellent video. Good information. Thanks for the effort you put into this.

[dennisrottmann]

You could use metal strapping across the coils, screwed into the wood to hold them down

[tipstosavedehumidifi]

great solar heater, thanks for sharing this video..

[NativeColoradoBoy]

So here we are almost 2 years later and I'd like an update as to how this is working and/or not working as we live in Montana and are looking for a pool heater. Also, if you like the wood heater over the poly wrap heater. let us know. Thanks!

[vasilicubagarcia]

Great set up man!! I see now that you have the wood heater as a back up for your solar heater. Now, I'd like to make some comments to improve a little bit your system. I remember from your wood fire heater video that you were having a flow rate of about 1 gpm through your 1/2" pipe and probably you would have wished to have a little bid more for a 15K gallons pool. Also I remember you saying that you would have preferred to have two coils in parallel for  a better efficiency so I wonder why you didn't apply the same idea to your solar heater set up (parallel setup). You have two main parameters that come into play here, velocity and pressure drop (head loss). You might want to keep the velocity between 5-10 ft/s in your system so you will have a reasonably pressure drop through out the system. The idea is not to overload your pump and keep the system pressure drop bellow your pump pressure limit for a given flow. You would need to check your pump's performance curve and make sure that your system's head loss falls under the dome of the curve, by doing so you won't damage at all your pump and will keep a good flow rate. I know I sound a little nerd but I won't limit myself to explain some theory, I will suggest you a solution in a minute as well.
Also, you would like to be able (ideally) to close fully your shut off valve and heat up 100% of your flow, but in your current set up you can't do it since you are reducing from 1 1/5" to 1/5" and keeping a single pipe (I suppose that your wood heater line is close) . If you shut off your 1 1/2" ball valve your pipe will probably burst. Your single 1/2" pipe won't handle such a huge flow very well and your pump might get damaged as well. It is also a matter of safety, if someone happens to be curious and close fully your valve without your presence, your system will go down. That being said, your solution would be having two or three 1/2" line (needs to be calculated) so that your system runs in parallel and instead of having your 1/2" hose in series, they should be in parallel. You will like to split up your entire flow in as many downstream connections as needed. Let me put you an example.
Most 1 1/2 pumps deliver as much as 150 gpm but if you utilized 1 1/2" pipe, your flow will be limited by the size of the pump. If you intend to maintain for example 6 ft/s in your pipe (to minimize head loss) the max flow rate that this pipe can handle is about 38 gpm (overrated pump). Then you put two 1" line in parallel to maintain the same velocity (two 1" line is equivalent of having one 1 1/2" line). Then, after each 1" pipe you put three 1/2" hose (equivalent to 1" pipe) to maintain again the same velocity. Now, these 1/2" hoses need to have the proper length so your pump can handle the total head loss in your system without reducing flow rate. Let's say for now that your are good with 50 ft. The result is having 6 x 50 ft solar heaters for your full flow and you can divert 100% of your flow, fast heating process, and safer too. If you want to divert only 50% because your are in a very hot day, close your 1 1/2' shut off valve half way and close fully the valve on your second 1" line so half of your flow rate will flow fully in your second 1" line, and you will have three solar heaters working in parallel (you have just shut down have of the system). 
I don't know what would be your requirements but is only matter of having access to your pump performance curve and calculate the head loss in your system so your pipe length and diameter can properly be sized. 
Hope my explanation will help you and I would gladly assist you in the calculations if you want (for free of course, lol). I'm currently designing my own solar heater by doing some of this calculation first. I'm a licensed professional engineer  so don't worry, I know what I'm saying and doing. I apologize if my English doesn't sound properly, I'm a foreign dude with just a few years living in USA.
I love by the way your videos and you are a genius. I wish I were as handy as you!!  
 
 

[nicholasphelps]

Can you leave water in it and shut off the diverter? If your pool was already as hot as you wanted and you don't want more. Or would it expand the tubing to sit there in the sun with no movement to the water?

[downyourtube]

This is a cool video. It made me think. Why don't you just put a really large black circle in the bottom of your pool? One, that could be easily removed and cleaned, simply by sliding it out. It wouldn't have to be a thick material. A light one would do. Made out of what I'm not sure, but it sound's a whole lot easier to do. You could even make something that floated on top of your pool to heat it up. A large solid circle of black with a few holes in it, just enough so the water would flow on top of it and that it still floated on top of the water. Seems to me whether its below on the bottom or floating on the top.. it be a good idea.
Nice video buddy. Have a nice day.

[lessenelectricityfor]

Love this!!! this would be a fun project this summer!

[leamyelectricinc]

Nice work. I also have both too. The fire heater is so much better then the solar heater however using both can really do the job depending on your situation. I learned a lot from your fire heater video and built my own. Thanks

[jaycharles]

Looks heavy. How do you empty the left over water for maybe storage during winter ?

[ponyboyack]

Are there worries about backflow into the heating system with a manifold design like that? I am a beginner, wondering about that.

[rodv]

I would like to make a suggestion. The frame and box where you have the irrigation tubing make it out of sheet-metal and squarer-tubing. The metal will absorb more heat and help heat the water.