Solar pool heating question

[trkinlv]

hi everybody,
I have a used solar water heating panel. its 10 feet long, 4 frrt wide and 6 " thick. it seems to br very well built but i can find no name tag. the panel has 1" copper tubing coming out on both ends . inside is 10 1/2" tubes, with fins between the 1" pipes. i want to use it as a pool water heater. now i understand that when you do this you are suppose to circulate the volume of the pool in 6 hours. so my pool is 20thousand gallons. so a little over 3thousand gallons an hour or 50 gallons a minute. the question: how big of a pump do i need to push that much water through this panel?
any help would be great thanks tim

[Mike90250]

50 gallons a minute.
how big of a pump do i need to push that much water through this panel?
any help would be great thanks tim

Will never get 50GPM thru the pipe. You are reading specs for large scale pool heaters, and with solar, you use what you have. You have 40 sq feet of collector area. for heating a pool, it will not make much of a dent.
I'd say to stick a 5gpm pump at the most, on it. That's about the flow from a small garden hose

[russ]

@ trkinlv - Welcome to Solar Panel Talk!

A rule of thumb for pool heating - 'The amount of collector area you need to heat your pool depends on a variety of factors, but a general rule of thumb is that the collector area should be equal to at least one half of the pool surface area in order to extend the swimming season into spring and autumn in a reasonably sunny climate.'

A lot of surface area is required for maximum affect. In Arizona you can possibly expect a better.

The North Carolina Solar Center has a good web site with information available for download - www.ncsc.ncsu.edu

[WildcatSolar]

4 years ago, I installed about 2000 ft of 1/2" drip line plastic pipe on my nearby roof. I plumbed it in with the regular pool pump with a valve to create just a little back pressure to force only a little of the water up through the lines and back down into the regular water flow. Pool pump is on an automatic timer and comes on when the sun has heated up the lines and shuts off when the sun starts behind the trees. The system raises the 9500 gal inground pool temp 8-10 degrees a day. Cools back some at night, but in four days I have gone from 50 degree water to 75-80 degree water. I have $300 bucks in the whole system up front and nothing since. The lines lay coiled up like flattened slinkies across a shingled roof and are secured with a strand of 1/4" nylon rope run through the coils. Works like a champ, cheap, and allows us to swim in upstate SC from late March through early October if we choose. We went from 4 months of time to 7+.

[Mike90250]

Watch that nylon rope. Nylon breaks down pretty quicly in the sun, poly rope lasts longer.

[Steve]

We've had a 24' round above ground pool for the past 6 years. 4 of those years used DIY solar heating.

I put a tap on my pool inlet pipe with a plastic barrel valve (I guess they call it) and a fitting for a common garden hose. I tapped the inlet pipe right after the chlorinator, where the water pressure is highest so it would flow through the (Relatively) thin hose.

I built a cheap table out of treated 2x4's with a sheet steel top. The table is 4x8' and had 400' of black garden hose coiled ontop. The output of the hose spilled out into the pool at a rate of maybe 1/2 to 3/4 gallon a minute. That may not sound like much but it is plenty- especially when used along with a commercial solar blanket. On a hot sun day you couldn't touch the water for the heat. The flow rate was controlled with the plastic barrel valve to suit the sun output.

I was advised by my pool supply company not to use any metal products such as copper or aluminum. They say some of the metal will naturally dissolve into the water and discolor my liner, especially if calcium in the water gets low.

We had the pump on a timer so it only pumped during the day. If it ran at night the coil of hose would act as a radiator and pull the heat back out of the pool.