View Full Version : Solar Panel Question for Above Groud Pool.............
Player101
07-20-2006, 09:49 AM
Hi:
I just joined the forum and I am new to pools and equipment, so I have lots to learn.
Anyway, I just installed an above ground oval pool (15x24). The installation went very well. I live in Ontario and we just had a heat wave, so the pool warmed up to about 84 degrees F, and has stayed around the 80 degree mark. The dealer I got the pool from last fall gave me a deal on a solar panel which I just got around to installing on the garage roof this past weekend. The solar panel is a FAFCO Solar Bear Economy System for above ground pools. The panel is 4x20 feet.
Here's my question; How much more heat will the solar panel supply the water in the pool? The last couple of days the pool has ranged around 82 degrees with water flowing through the panel. Now, I am not sure how much the solar panel contributed to the heat as the air temperature could have helped that out also. From what others told me I should see a 5 degree jump in temperature. Did I waste my money getting a solar panel when the hot weather could have done the heating for me? The dealer and literature I read mentioned that I only need one of these panels for the size of pool I got, but should I have bought 2? Anyone, have any experience with this solar panel; how much heat should be expected to gain from it and over how much time. Also, there is a red handle valve built into the solar panel. I read you should turn this valve so that the pressure is increased to 5 to 7 psi, so the water flows slower in the panel presumably to pick up more heat from the sun. Would this be correct, or should the valve be fully open during sun light times for maximum flow.
Sorry for all the questions, but I am new and would appreciate anyone with some suggestions or answers.
Thanks,
John
matt4x4
07-20-2006, 10:15 AM
Hi John,
I'm also in southern ontario, here are my stats and observations.
pool - 30 foot round - 22,000 gal - 100,000 Liters
I'm supposed to have 3 sets of these panels, but only have one.
No flow control - just full flow
Pool temperature has been ranging from 88 degrees to 94 degrees with solar panels hooked in. (wife likes it to be a hot tub)
Use solar blanket during day as well to stop evaporation (on a well).
Pool in full sun, panels on ground beside pool facing south also full sun.
Water gets circulated from 9:00am to 7:00pm.
Neighbour's pool - 24 foot round, no solar, full sun exposure, same solar cover usage for same reasons - pool is 6-8 degrees cooler than mine.
Here's what I can tell you about running your panels.
Don't bother restricting the flow, slower flow does not mean more heat, slower flow means higher increase in temerature of the water passing through, however, there will be heat lost to outside factors. The faster you can transfer the heat from the panel to the water the better off you are, trickling the water actually allows for more heat loss from the panels back to the air or into your roof shingles.
If your panels feel cool when the pump is on, they are working - because the water absorbs all the heat drawn into the panels.
If you restrict the flow, you create more wear and tear on your pump.
Do not run water through panels at night, they will work in reverse - cooling your water.
use a solar cover at night to retain yourt heat gained during the day.
One panel is plenty for your pool.
My pool gains approximately 3-4 degrees over the course of a full sun day, it loses about 1-2 degrees over night. Yours should gain a little more because you have much less water to heat. (of course your panels have to be set identical to mine for a direct comparison).
Somehow, your numbers tell me your panels are not working or not working very well, unless you recently put up the pool and are just coming up to the right temperatures from frigid fill water. Or, your system is running at night effectively cooling your pool, so any/all heat gained is lost over night.
Player101
07-20-2006, 10:51 AM
Thanks for the information and quick response matt4x4. I am actually in northern Ontario, but I believe we have been getting similar temperature and weather as southern Ontario; although it may not be as humid in northern Ontario.
In your last paragraph you mentioned my panel may not be working well, I am suspecting that also, as I expected a larger temperature increase. Basically, the pool is getting up to day time temperature. If it's 80 degrees in the air, the pool basically gets to 80 degrees. I thought I would be able to get more temperature from the panel. At least 3 to 5 degrees above air temperature on a full sunny day. My panel does feel cool to the touch when water is going through it.
I got my pool up in the beginning of July in time for the heat wave to hit (we got like 90 to 100 degree days for a week), so the pool warmed up quickly. It contains about 34 500 litres
I should maybe try opening the built in valve to fully on for maximum flow through the panel as you suggested. The panel is mounted on my garage roof, so it gets ful exposure to the sun from sunrise to sunset. There are no trees or tall buildings to shade the pool or solar panel. I haven't been running my panel at night or on cloudy days. The only thing I haven't been doing is covering the pool with the solar blanket. Maybe this is why I haven't been seeing a gain in temperature? Would I gain 5 degrees if I used the solar blanket?
Thanks again for your time and information…..John
PS: Not sure if this helps in determining if my panel is working, but the other day when I turned on the panel after a few hours of sun in the afternoon, I ran over to the pool and put my hand over the water outlet; the water was very warm for the first few minutes as it transfered the water that was sitting in the panel during that few hours to the pool.
mkelley
07-20-2006, 11:50 AM
And it *is* south facing, right?
It makes a tremendous difference if the panels are facing the south sun -- mounting the panels northfacing (even if the sun hits them all day long) will not be nearly as effective (optimum tilt is around 30 degrees if I remember right, but you can easily look this up).
matt4x4
07-20-2006, 11:51 AM
Panel is working fine, but yes, open the valve fully.
Now that I know you're up north, I can tell you there WILL be big differences, the humidity down here actually helps keep heat in the pool (less evaporative cooling). My pool gets this warm because we have 100% humidity.
With the breeze you probably get up there and less humidity, you're cooling your pool while heating your pool, thus less gain, a solar blanket will help you quite a bit with retaining the heat.
Wind blowing over your panels will also cool them some making them less effective.
You're doing pretty good though, getting your pool up to 80 on a day that only has a high of 80 or so, my pool never gets warmer than air temperature, unless the sun starts setting :)
larry b
07-20-2006, 12:10 PM
i have a 28ft round ag pool i also have that solar panel with the red handle mine is faceing south and laying on the ground, it raises my temp about 3-5 degrees i love it,as far a pressure it only goes up a couple of pounds when i open the red handle. use it when its sunny and close it when its cloudy its that simple
Player101
07-20-2006, 12:13 PM
Hi mkelley....The panel is facing south....actually it is facing due south and gets sun about 90% of the day on the garage roof. The garage roof is a truss roof so the panel is on an incline installed on the roof shingles (whatever angle the truss roof is at).
Matt4x4....thanks for confirming my panel is working fine....I will try the panel with the valve open fully to see if that makes a difference (with the valve open it only increases my gauge by 2 PSI). We do get a lot of days with some wind as I am near Lake Superior. The last few days we have had day time air temperatures in the 80s, but the evenings have been going down to 58 to 62 degrees. I will definitely start using the solar blanket to decrease heat loss at night.
cheers..John
mkelley
07-20-2006, 01:15 PM
The rule of thumb is that if nighttime temps drop below 60 you need a cover or you just can't make up the heat loss with solar no matter how oversized you get it. So, yes, if your evening temps have been as you describe I'm guessing that a solar blanket will help you tremendously.
tribe_fan
07-20-2006, 07:02 PM
I have that exact same panel - and you should be able to feel the warm water coming in the return when the sun it out. The panel itself should be cool when pumping water through it. If it is hot it means the valve is closed or defective. The valve itself is kind of a PITA - mine is on the ground and it gets bumped of moves on its own. I'm in northern Ohio. My pool water got up to 92 this week. (18 x4 ).