DIY Solar Heater

[Imjustingraham]

Hi everyone,

New to pool ownership as of about 2 years ago. Last summer I built a very quick DIY pool heater and decided this year that I would build a new one to make it look a little nicer. I have an intex above ground pool and live in central Alberta where we don't have an ideal pool season so I wasn't looking to spend a ton of money. I thought I would share my pictures in hopes it would help someone else that was in the same boat as me. The project cost about 260 Canadian (210 USD) and I spent an evening and half of Saturday on it.

The proof is in the numbers though, it's early in the season here with our days being about 77 F and our evenings as low as 48 F.

The pool was 69 on Saturday when I hooked it up and after two average days it is up 5 degrees to 74. I'm quite happy with that return.

I started by sandwiching a 4 by 8 sheet of metal backed styrofoam insulation between a 4 by 8 sheet of particle board, and a frame I built out of 2 by 2s. Then painted it black to maximize the heat.

I then coiled 200 feet of black poly tubing into each side of the box I built. It was a bit difficult at the end, I definitely recommend having a buddy and some cold beers on hand.

Next came the cover. I chose to use a corrugated plastic like they use greenhouse. Hopefully it won't yellow too much.

We lifted it onto the roof Saturday morning, and added strapping underneath so it wouldn't collect water against the shingles.

Then it was a bit of plumbing to get the pump to push the water onto the roof. I first used a dishwasher Y but couldn't get enough pressure.

I had to step down my pump from the 1 1/2 abs I had run so it would pump on the new line too. Flow is still adequate and the pump is running about 10 psi.

I put in a clear return line so I could monitor flow.

If you have any questions feel free to let me know.

Justin

Sent from my iPad using Tapatalk

 

[DarrelB]

Nice job, glad to see its working out for you.

 

[jblizzle]

Welcome to TFP!!!

Glad it is helping, but I should point out that solar heating is all about sqft area exposed to the sun. At best you have about 32 sqft, the clear cover may help a little. Just looked at Ebay and for what you spent, you could have gotten 80 sqft of pool solar mats ... thus doubling the heat input you could get to your pool. Plus the mats run many many many parallel runs of small tubes which are more efficient at adding heat than a single coiled tube.

It just does not make a lot of sense anymore to DIY when the mats have gotten so inexpensive ... although there is something to be said for pride of the accomplishment.

 

[Imjustingraham]

Hey jbizzle, thanks for the input. I will admit I don't know a lot about solar heating, but I got the idea from some of the smaller coiled solar heaters. One of my concerns about the solar mats is that I don't have a lot of area with south exposure to work with aside from the lawn. Along with the fact that we have fairly mild summers I hoped to get a greenhouse effect with this project. I am not sure where you are from, but we don't have ideal pool weather around here. I only know two other people with pools, and both of them are indoor.

Overall I am happy with the project and hopefully it will work well.

Justin


Sent from my iPhone using Tapatalk

 

[Isaac-1]

Glazed style solar panel boxes like you have built do better when trying to heat water more than about 15-20 degrees F above above the ambient temperature. At less than 15 degrees above ambient unglazed collectors like the black plastic mat style collectors absorb much more of the available heat from sunlight.

Let me put some numbers to that, assume you are wanting to heat your pool to 90 degrees F (a bit warm in my opinion, but some people like a warm pool), then the optimal choice of collector types would be an unglazed mat is your daytime average temperature was above about 70 degrees F. Only if your daytime average temperature is below 70 degrees F would a glazed panel provide superior performance. (of course if you prefer you pool at 85 degrees F the daytime average temperature would move to to about 65 degrees).

Ike

p.s. I forget the exact numbers, but under optimal conditions the unglazed black plastic mat collectors absorb close to 90% of the available heat from sunlight, by comparison glazed collectors have a peak performance in the 60-65% ballpark, a large amount of that lost potential heat is lost simply from reflection off the glazing, another big chunk is radiated from the glazing, leaving only what passes through to get absorbed by the tubes. Glazed panels do have their place in colder climates where you have massive panel arrays for pools in the colder months, and for domestic hot water where you have a higher temperature difference.

 

[Imjustingraham]

Thanks Isaac-1, glad to hear I'm on the right track. 70 to 75 is a pretty average temp with our hottest days around 85. I didn't ever expect to make the pool warm, I just wanted to take the edge off which the 5 degree difference I've seen so far has done. I don't think my pool got warmer than 71 or 72 last year so 73 this early is quite promising [emoji106]


Sent from my iPhone using Tapatalk

 

[pooldv]

Here's to warmer pools!

 

[POPPA S]

that black tubing is a *** to work with, Highly recommend beers and a friend!!!!!!!

 

[Imjustingraham]

@POPPA S , there are so many words I could fill those stars with haha


Sent from my iPad using Tapatalk