How to Build a DIY SOLAR POOL HEATER for Less Than $100 | Swim University

If you’re looking for a cheap, energy-efficient way to heat your pool, making your own solar pool heater is a great option. Not only can you use the power of the sun to heat your water, but the whole project will likely cost less than $100. Here's a step-by-step guide on how to build a DIY solar pool heater.

⏰ Timestamps:
00:00 - Introduction to How To Build a DIY Solar Pool Heater
00:42 - How Does a DIY Solar Pool Heater Work?
01:10 - Supply List for a DIY Solar Pool Heater
02:57 - Optional Supplies for a DIY Solar Pool Heater
04:17 - How To Make Your DIY Solar Pool Heater
06:29 - Troubleshooting a Solar Pool Heater

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Have you tried to build one of these before? Let us know in the comment what's worked and what hasn't! And if you need more pool maintenance help, grab the free Pool Care Cheat Sheet at

[chrisbvt]

I built one for a 4500 gallon pool last summer. There is no way you will be able to coil 200 feet of tubing in a 4X4 box. I was able to get 100 feet into a 5X5 box. I painted everything black and topped with thick crystal clear vinyl (look for clear vinyl tablecloth). I used a non-submersible pump at 4 gallons/min. It did do something, but it only a few degrees more than just the pool being in the sun. I improved upon it this year by adding 12 feet of copper baseboard heater fins in the box on top of the coils (leftover from home renovation). I painted it all black and added a loop through heater fins before the coil. I also added four small computer fans to keep the air flowing through the fins when the pump is on. This really increased efficiency! On a cool day in the 60s, with the sun shining, I get a 10 degree rise in the pool, even though air temperature never even gets up to the pool temperature. We were swimming in an 80 degree pool this year during the last week of June (In Vermont!) I automated it with Hubitat and a temp sensor in the box. Pump comes on when box temperature gets to 80, and goes off when it drops below 80. Doing it again, I would scrap the hose coil and use only baseboard heater fins, filling the whole box, but that gets very pricy if buying new.

[ebdmqeq]

Built a shallow box, painted interior black and covered it with clear corrugated plastic sheeting. You must use GFCI receptacle for your pump supply. By using a garden hose splitter on the outlet of the pump, i can bypass a portion of the flow back into the pool and get better retention time of the warming water in the solar collector.

[doctordutch]

Can you redirect the water from your pool pump to coils (before or after its been clean) instead of a seperate sump pump?

[RichardBaileyrichoncode]

Mostly followed this. Used 8 lengths of electric fence ribbon in pairs (across, vertical, and diagonals) to weave above and below each pass of pipe. It was easy, fast, cheap, and very secure.

[SolarProjectsSweden]

Nice video filled with good tips & trix. I'm setting up a solar powered pool heater right now and my goal is 30°C / 86°F in the pool. I'm starting with 250 meters / 820 feet of 20 mm / ¾ inch PEM hose in a flat rooftop setup. A 20V rainwater barrel pump (2, 000 liters - 528 gallons / hour) will be connected directly to a solar panel, so it's a completely automatic system controlled and powered by the sun.

No sun = no pump = no heating.

Since I'm located at 60° latitude in the northern hemisphere, I'll guess it'll be some problems and math to solve along the way, but it'll be fun.

Keep up your good work

[kenmathews]

I have made a heater years ago with copper tubing painted flat black and incased in a glass covered box. It worked very well.

[makeandbreak]

If you don't wrap it in clear tape, if you paint the inside white, it will be warmer than a black background by a good amount. Black absorbs heat so it will just make the plywood warmer instead of reflecting it to the back of the tubing.

[Carl_in_AZ]

💦I use a 5W 12-volt solar panel and Rule 1100 GPH 27DA standard submersible bilge pump connected to a roll of PEX tubing mounted flat on 4x4 foot 1/4 inch plywood all painted black with Plastic Dip. This keeps my spa warm so I use very little propane in the winter to heat it up quickly to104F.💦

[moniquewarren]

I plan to try this this week before the holiday along With a solar pool cover. I’ll try anything to avoid a cold pool 🥶

[kiabass]

I'm gonna build one and just hook it up to the pool pool return hose

[BradySzabo]

instead of a sump pump at the bottom of my pool, is there a way I can just add a 1.5" to 2" PVC Pipe (so the kids aren't banging into the pump in my round pool? I think it would better to be out of the way and close to the wall if possible? Thanks. I subscribed last week and have learned so much about pool systems. I am going with the saltwater system, a little nervous, but I bought the Saltwater 8000 and it arrives next week. I still need my chlorine generator and see what you mean by upfront cost being high. Any recommendations on a chlorine generator that you like?

[rs-vlim]

What if you just used 200 ft or more of black garden hose hooked up to a sump pump?

[pamdiprima]

Awesome idea. I've got grandkids coming next week, but although it's warm outside, pool water is still a bit chilly for swimming. I'll give this a go this week!

[gisellellanes]

Times like these I’m glad I’m in Florida and our down time is only a few weeks 😮‍💨

[dantheman]

Whats the math to figure out what size pump I need? I built this with about 400' of line and a 75gph pump won't push it through. Thanks

[ThePizzaman]

How long do you run the sump pump each day?

[shellstachowicz]

Do you just unplug the pump when you swim?

[matthewgarrett]

What size hp submersible pump is recommended using 200ft of 1/2 PEX tubing? Would 1/2 hp be appropriate?

[terrilhargrovejones]

Thanks for the tip! I don't want anyone here past Labor Day, so there's that...😅😅😅 My 16' x 32' inground pool gets full sun all day on a sunny day, so that by the early evening, it's like being in a bath of very tepid water.