Solar heat for pool

[messmaker]

Anyone have any experience with solar heat for an above ground pool? I only have a couple grand for the project so a $5000 attic heater is out of bounds.

[poolhound]

I live in AZ so we are not short of sun or HEAT!!! I have solar heated hot water and it works really well especially in the summer. Heating a pool is a very different matter. The issue is how much water you have to heat and how quickly plus how quickly it will loose the heat

My pool is approx 30,000 gallons and I did look into it once and it just wasnt worth it. Most work as heat exchangers (thats how my hot water system works) and for an 80-100 gal hot water tank thats great, not so for 1000s of gallons. We obviosuly dont need the pool heated here in the summer more the opposite actually but I was trying to get it extended in the shoulder seasons. As I mentioned above the pool temp is more about heat loss than gain. As a general rule of thumb the water temp of our pool tends towards they daytime low temp so in the height of summer its around 95 degrees. because we have such a wide temp swing in the spring and fall we may get 90 degree days but the night time temps drop to the 50s so any gain from the sun disappears at night.

IMHO I would just invest in a good solar heat cover (some are like bubble wrap material). This helps to magnify the suns heat but more imprtantly helps keep it in at night. They claim you can get a 10-15 degree benefit.

Bottom line is it really depends on how many gallons, what the surface area is and how much night time heat loss you may expect.

hope that helps a bit at least

[DaveS]

Anyone have any experience with solar heat for an above ground pool? I only have a couple grand for the project so a $5000 attic heater is out of bounds.

When I lived in Florida, I had a neighbor that made his own pool heater out of metal roofing, a couple sheets of lexan, and a whole bunch of pex pipe (I think) painted black.

He built a box, with the metal roofing as the bottom, it was big - like 4'x6'; he put in on the flat roof of his shed (he had it propped up at an angle with a couple milk boxes). He ran two 2" pipes into the box, and connected a whole bunch of coils of the flexible pipe in between the two 2" pipes (one in, one out). He covered the top with the sheets of lexan.

He ran his inline with his pool pump - which I suspect was hard on the pump. But you could get a cheaper pump off of ebay I suppose, and use it separately.

It sure was ugly.

He claims it heated his pool up nicely... I was suspicious.

[OpaDC]

I used the bubble cover for a coupe of years but IMHO was more trouble than it was worth. Maybe 5 degrees difference at most. My neighbor had a roof mounted system that pump water up through the black plastic (? not sure of material) and back down to pool. When a hurricane removed it for him he joked that it saved him the expense of doing it himself. The main problem always seems to be cooling at night. As poolhound stated, on shoulder season temp can change lots over night. I have seen mine drop off as much as 10 in spring when a cold front comes through, from 83 to 73. The bubble cover DID help some with this when I had it. It may have been more worth the trouble if I had owned a spool to roll it up with, but I don't think so.

[eccentrictinkerer]

I installed one of these two years ago for my 16' round above-ground pool. And it works great! In Minnesota!



I got it from www.waterwarehouse.com. I placed the collector on the roof of my 2 1/2 story house (uff da!) and used a little 1/2 hp pump from HF to circulate the pool water. The pool pump was not up to handling the lift required.

Last year I had to plug 4 of the water channels because I hadn't drained the water out and some of the channels burst, so I lost about 15% efficiency.

I get a delta (difference between water temp in and out of collector) of about 2 degrees max. but I can maintain 80+ degrees all summer (if we get sunshine 4 or 5 days a week).

We like it so much that I ordered another unit to go in series with the first so we can warm up the pool faster. Of course a good solar cover is a must to keep evaporation and loss of heat to air.

My initial investment was less than $250 but we got $1000's of enjoyment. It costs about 50 cents to a dollar a day to run the little pump.

Only one drawback. The grandkids are here almost everyday and can they ever empty the 'frig quick!

BTW, I built the pool out of treated plywood 17 years ago! But that's another story!

[maxparot]

As another Arizona resident I too have looked into using the sun to heat my pool.
Turns out that at least here that an automatic pool cover may be a better bang for the buck. The reason is the evaporative cooling effect that works to cool our homes in the drier months works against our pools in the spring and fall when the nights are cool. Add an automatic cover and it can eliminate the surface evaporation and it's cooling effect. However the pool must be exposed during sunny daylight hours to absorb the suns warmth.
Once you have an automatic cover in place a solar pool heater is more effective if properly sized for the pool and given enough exposure will do a fair job in the curtain regions. Like here in AZ.

[kevinsa]

I just recently helped a friend do this with her pool here in San Diego. The single most important thing is a pool cover. The cooling effects of evaporation just can’t be understated. You need a good pool cover. For the solar heat we used a thousand feet of one inch black poly irrigation tubing. It comes in 500 foot spools for about $90 each. We put two T fittings off the pipe out of the sand filter with a ball valve in between them. Off each T is another ball valve. One T is the inlet for the poly tubing and the other T is the outlet. The ball valve between the T’s allows you to control how much water goes through the poly tubing. This setup allows you to totally cut out the solar heater when needed. We just put the poly tubing in a giant coil on the garage roof and tied each loop together with UV resistant nylon zip ties. Having a flat roof to put it on helped. For less than $250 we got a system that puts out water too hot to touch on a sunny afternoon. The next step will be to put in an auto switching valve. For about $350 you can get a solar heater switching valve made specifically for this task. It has sensors for the pool and solar heater and will turn on the pump and direct the water to the heater when conditions are ideal and bypass the heater when it’s not.

[messmaker]

I just recently helped a friend do this with her pool here in San Diego. The single most important thing is a pool cover. The cooling effects of evaporation just can’t be understated. You need a good pool cover. For the solar heat we used a thousand feet of one inch black poly irrigation tubing. It comes in 500 foot spools for about $90 each. We put two T fittings off the pipe out of the sand filter with a ball valve in between them. Off each T is another ball valve. One T is the inlet for the poly tubing and the other T is the outlet. The ball valve between the T’s allows you to control how much water goes through the poly tubing. This setup allows you to totally cut out the solar heater when needed. We just put the poly tubing in a giant coil on the garage roof and tied each loop together with UV resistant nylon zip ties. Having a flat roof to put it on helped. For less than $250 we got a system that puts out water too hot to touch on a sunny afternoon. The next step will be to put in an auto switching valve. For about $350 you can get a solar heater switching valve made specifically for this task. It has sensors for the pool and solar heater and will turn on the pump and direct the water to the heater when conditions are ideal and bypass the heater when it’s not.

I have looked into doing something like this as I have about 300' of black chain link fencing that runs beside the pool. I am thinking that 500-600 foot run might be the ticket and would not be as ugly as the big black solar panels that seem to be the next best solution. I already have a pool cover and my pump is on a timer so it only runs during the middle of the day. I just need a bit more of a temp boost to overcome nightime temp loss and a bit of A.M. shading.