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jcpbnp
04-05-2006, 07:42 PM
Wasn't sure where to post this, so here it is. I live in San Antonio and my pool is in direct sunlight. During the summer the water gets up to 96 degrees which is way to warm to enjoy. Any recommendations on how to keep it cooler? I know they make a solar cover to keep it warmer, but do they make something to keep it cooler?

waterbear
04-05-2006, 07:45 PM
about the only thing I know of is a reverse cycle heat pump that will cool the pool in warm weather and heat it in cold weather. I have an aquatemp Icebreaker but I don't know how good it is at cooling because I have not gone thru a full summer with the pool operational yet (Even thought it WAS supposed to be completed LAST June!) Works great at heating though!. As an alternative, you could tell your family and friends that it isn't a pool but a very very big hot tub!

Brock
04-05-2006, 09:58 PM
The other way to lower the temp is run a foutain to get the water in to the air at night. You will loose more water, but it should encourage heat loss when the air cooler then the pool.

aylad
04-05-2006, 10:17 PM
I live in Louisiana, and my water temp stays in the 90s for a good part of the spring and summer. I started running my pump at night instead of in the daytime, and that helps hold it down some. Also, I have a slide, and leave the water running on the slide while we're in the pool, and you'd be amazed at how much cooler the pool gets..

Janet

fog80
04-06-2006, 01:50 PM
wow, pool water in the 90's.

my stupid neighbor has these huge pine trees right along his side of the fence and they cast a shadow over the pool after noon.

it sucks because the water temp never really gets too high.

PoolDoc
04-06-2006, 05:10 PM
I live in San Antonio and my pool is in direct sunlight. During the summer the water gets up to 96 degrees which is way to warm to enjoy. Any recommendations on how to keep it cooler? I know they make a solar cover to keep it warmer, but do they make something to keep it cooler?
Hi jcpbnp;

Just to let you know, this probably should go into the Pool Ops section, so I'm going to move it there shortly.

Meanwhile, back to your regularly scheduled question:
Contrary to myths I periodically see on the net, ice won't work . . . unless you bring truckloads! A couple thousands of pounds of ice just doesn't have enough 'coolth' to remove all that heat in a 10,000+ gallon pool.
Reverse heat pumps could certainly work, but don't count on it, unless you confirm that function with the manufacturer for YOUR area, YOUR size pool, and YOUR heat pump.
Sprayers work, but how well depends on lots of variables. In dry air areas (AZ, NM, etc.) a sprayer can cool the pool a LOT, by evaporating a LOT of water. This in turn tends to concentrate the salts in from fill water that's already saline . . . and you are off and running toward a whole new set of problems. In wet air areas (FL, LA, MS), spraying during the day may not be too effective. But, high volume sprays at night, when the air is cooler can make a difference without evaporating much water.
Solar heaters -- really -- can also work, if you circulate the water at night, when temps are lower and there's no sun. They'll work best when night skies are clear, and if you can keep them from contact with heat storing surfaces like concrete or thick roofing.But . . . there's little data on how to size the things that will work, so it's really hard to predict how well they will work. Your best bet is probably to start with things that are cheap and easy (like night operation of fountains quick connected to pool inlets) and test for yourself.

Of course, if you do, I'd love it if you could report results back here.

Ben

duraleigh
04-06-2006, 07:03 PM
Here's food for thought:

I intend to divert my return water through a "cooling field". (You gotta' have a lot of room to do this) Once I can find a deal on 700' of 3/4" copper pipe, I'm gonna make a manifold and take my 2" return line into 7 - 100' runs of 3/4" copper. I'll bury those 7 pipes about 6" apart and 4' deep. By the time my return water makes it's journey through the copper and comes back together (joining my regular return lines), I'm hoping my return water temp will be around 80 degrees. The only thing I can't quite get a handle on is how well the surrounding soil will dissipate the heat given off by the copper pipes. If I cannot dissipate the heat quickly enough into the surrounding soil, my returning water temp will not get low enough to effectively lower the temp of the whole pool.

This experiment is waaaay too pricey with new pipe. I've been looking on the net and locally for something surplus....nothing yet...I'll post the results when I find the pipe!!:) :)

waterbear
04-07-2006, 10:17 AM
Copper pipe? Aren't you afraid of the possiblility of introducing copper into your pool?

duraleigh
04-07-2006, 10:32 AM
Copper pipe? Aren't you afraid of the possiblility of introducing copper into your pool?

Nope! Just as if I had a pool heater, I watch my pH.;)

Dave S.

CarlD
04-07-2006, 12:34 PM
Running solar panels at night is nice and simple. They act like a car radiator.

rdietman
04-08-2006, 04:10 AM
wouldnt pushing the water through all that small diameter pipe cause some pump head problems??????

duraleigh
04-08-2006, 08:14 AM
wouldnt pushing the water through all that small diameter pipe cause some pump head problems??????

If you don't use enough of them, yes. The seven 3/4" pipes is slightly more cubic volume than the 2" pipe feeding them.

I need the multiple pipes for the increased soil contact for heat dissapation and am willing to trade off a little TDH to get it. I'm thinking it will add about 2-4psi max to my pressure.

Dave S.

jcpbnp
04-10-2006, 10:44 AM
Thanks for all the information. I'm not sure I understand how solar panels work but was is the approximate cost of having them installed?

CarlD
04-10-2006, 12:31 PM
Thanks for all the information. I'm not sure I understand how solar panels work but was is the approximate cost of having them installed?

It's very simple....A large flat black plastic panel has lots of little tubes running through it. Pool water is pumped in one side, cools the panel, and is pumped out the other side, back into the pool, carrying the heat it leached from the panel with it. Think of how hot a black, asphalt road gets--it will burn your hand. The panel would get that hot too, but all the water flowing through bleeds off the heat and keeps it cool enough to touch, sometimes even cool, even on the hottest days.

The more water you can flow through that panel, the more heat you can bleed off into your pool. It's a matter of transferring BTUs, not temperature. A BTU (British Thermal Unit) is the amount of heat energy necessary to raise one pound of water 1 degree Farenheit.

Its metric equivalent is the calorie (actually kilo-calorie) and, yes, it's EXACTLY the same calorie as used in food and dieting. A (Kilo-) calorie is the amount of heat energy needed to raise one kilogram of water 1 degree Celsius. They actually burn the food to measure the caloric output...

A solar panel works EXACTLY like your car radiator works, only backwards. Your radiator takes the hot water from the engine and exposes it to cool air, cooling the water and keeping the engine from melting. So if you run your solar panel at night, when it's cool, it will cool your pool (if the pool's too warm) in EXACTLY the same way.

I don't know the cost of installation. I've only installed them myself, or had them as part of the pool's installation (FantaSea pools). I suppose it depends on how fancy you want to get. A roof-top system that's winter-proof, with bleed valves and computations of how much pump pressure is needed is going to cost a heck of a lot more than having a guy just set up roll-up panels on the ground and plumb them in.

prh129
04-11-2006, 12:58 PM
I don't know how effective this would be but should be inexpensive enough to try. Suppose you get a large white tarp, cut it to size and use it as an anti-solar cover? It should reflect most of the sunlight when its in place. If it works, you could market it! (unless someone already has).

Peter

PoolDoc
04-13-2006, 09:37 AM
Suppose you get a large white tarp, cut it to size and use it as an anti-solar cover?

The problem, as with solar covers, is the need to wrestle them on and off 2x daily. From what I've seen, about 75% of cover purchasers end up parking them in a corner for a year or so, before they give it up, and toss them.

A thin white poly cover would be harder to handle than a solar cover. A yet more effective silver Mylar cover would be even worse to handle, and all but impossible in even a slight breeze. An aluminized automatic cover might be cool, though.

Ben
PoolDoc

dalparadise
04-15-2006, 01:11 PM
I live in Houston and have similar water temp issues, as you might imagine.

The best thing I've found is to avoid running your pump at the hottest point of the day (or at least when the sun is directly overhead) -- 12-3pm, or so. Note that radiant heat from the sun is much more effective in heating your pool water than air temp. So, even though it's usually hottest here in Texas around 5pm, or so, the sun is not directly overhead.

My pool is on the north side of my house, so the sun tracks across it all day long in summer. I got 94 degrees every day in July.

Toward the end of summer, I planted some 8' Mexican fan palms on the western edge of the pool to cast long shadows after 5pm. That has helped.

With night filtering and some shade, I'm thinking I'll get 91 degrees this summer -- which is enjoyable for me.

Good luck!

WagonPilot
04-23-2006, 04:57 PM
A solar panel works EXACTLY like your car radiator works, only backwards. Your radiator takes the hot water from the engine and exposes it to cool air, cooling the water and keeping the engine from melting. So if you run your solar panel at night, when it's cool, it will cool your pool (if the pool's too warm) in EXACTLY the same way.


Not to pick a nit, but it's not EXACTLY the same. The car radiator (dispite its name) is actually utilizing convective heat transfer, while running the solar panels at night is primarily a blackbody radiation transfer.


James

CarlD
04-23-2006, 09:27 PM
Yup, that's a nit. The car radiator uses radiation--and the fan moves it away when the car is idling.

Still, it DOES function at night in a similar fashion...

shippy1973
06-06-2006, 07:35 PM
I live in Houston and have similar water temp issues, as you might imagine.

The best thing I've found is to avoid running your pump at the hottest point of the day (or at least when the sun is directly overhead) -- 12-3pm, or so. Note that radiant heat from the sun is much more effective in heating your pool water than air temp. So, even though it's usually hottest here in Texas around 5pm, or so, the sun is not directly overhead.

My pool is on the north side of my house, so the sun tracks across it all day long in summer. I got 94 degrees every day in July.

Toward the end of summer, I planted some 8' Mexican fan palms on the western edge of the pool to cast long shadows after 5pm. That has helped.

With night filtering and some shade, I'm thinking I'll get 91 degrees this summer -- which is enjoyable for me.

Good luck!

Ok... I am resurrecting this older thread because I am in the same spot as the original poster. I, too, live in SA and today I looked and my temp was already 86. So... you are saying that I should run the pump from about 8AM-12PM and have it shut off? I usually add my bleach at about 8PM and the pump shuts off at 12AM so I could turn it back on then. I would get my 8 hours a day and miss the hottest part. Does that sounds reasonable or is that too long between? This is not a HUGE deal but I don't want 95 degree water by the end of the week (suppose to be high 90s for the next 4-5 days...)

estonb
06-10-2006, 03:25 PM
I am in S. Texas - same problem.

I've often thought about what adding dry ice the pool water would do to it. It is certainly cold enough, but I can't find anything that tells me what (if any) chemical changes it might make to the water.

Any ideas?

Tpope
06-10-2006, 05:42 PM
I live 20 minutes south of SA. Next week is going to get to 106 here so watch out!

waterbear
06-10-2006, 05:47 PM
I am in S. Texas - same problem.

I've often thought about what adding dry ice the pool water would do to it. It is certainly cold enough, but I can't find anything that tells me what (if any) chemical changes it might make to the water.

Any ideas? might raise the TA and/or lower the pH. The carbon dixoide will dissovle in the water and form carbonic acid which is part of the TA buffer system and also has an impact on pH

Tpope
06-10-2006, 06:22 PM
Here is an idea. If you buy a hot tub air pump and plumb some pvc together with a horizontal pipe running about 10' along bottom of pool several holes drilled in it and an end cap you could cool the temp during the night possibly. I get this idea from a friend who has hooked up the same stuff to steel pipe running through his wood burning stove and the heated air then is blown into house with the hot tub pump which you can control the speed of.

gwrace1
07-19-2006, 10:36 AM
Deleted as merchant has unfair business practices.

les_smith
07-19-2006, 09:36 PM
My pool water is 94 degrees right now. I use our fountain when we swim and take it off when were not. It doesn't lower my pool water temprature, but it sure makes it feel a lot cooler when we are in the pool.

tclemmer
07-20-2006, 09:44 AM
Anyone have any experience with one of these evaporative cooling systems?

http://www.mistcooling.com/pool_cool.htm

For $36 bucks it may be worth a try. Our water temps here in south Texas yesterday were at 96 degrees. Talk about a large hot tub...:)

David

Not sure it would work but it is cheaper at
http://www.poolcooler.com

Tom

PatL34
07-20-2006, 12:34 PM
I would have thought that a couple of cooling fans run at night over the pool surface to help evaporate the water would work.

Advantages are:

1. Don't need to run the pool pump.

2. The air temps at night are cooler.

3. The higher water temperature helps to increase the evaporative effect.

Just make sure that the fans are connected through a GFCI outlet.

Hope this helps.

Pat

duraleigh
07-20-2006, 12:54 PM
Ya'll may have missed this thread about evaporative cooling....it works.

http://www.poolforum.com/pf2/showthread.php?t=4243

VOLDADDY
07-20-2006, 08:46 PM
Not sure it would work but it is cheaper at
http://www.poolcooler.com

Tom

I just ordered 2 of these devices. I hope they work as advertised. I will post back my experience with them and let you know if they work or are bogus.

VOLDADDY
07-27-2006, 08:32 PM
I received the pool cooling devices today. I will try to install them tonight and see what they do. I will let you know. BTW-if you buy 2, the S&H is free.

ChuckD
07-28-2006, 12:20 AM
People talking about heat pumps to cool the water got me thinking about heat pumps, and then about geothermal sources, and then about the possibilty of using a ground loop much like a GT heat pump would use to either lose, or gain heat. The kind I'm thinking of would be a well-type that would hold a U tube segment of the filtration system. No heat pump, just circulate the water into the ground where it's always 50-55 degrees. The technology's already proven. It would just need to be adapted to run pool water thru instead of coolant which would be trivial and well drillers are a dime a dozen.

We're just now rejoicing that the water temp has finally hit 80 so this isn't anything I need, just thinking out loud.

C.

tclemmer
07-28-2006, 02:19 PM
I received the pool cooling devices today. I will try to install them tonight and see what they do. I will let you know. BTW-if you buy 2, the S&H is free.

I will be interested to see if they work.

Keep us informed.

Tom

VOLDADDY
08-02-2006, 10:07 AM
I had to go buy one of the keys to remove the pipe at the returns. I will do this tomorrow. It has been in the high 90's with heat indexes of 105+. We had a few days that weren't sweltering heat, along with some rain, and my pool came down to a refreshing 84. Now I'm sure it will be back to 90+. I will post back and let you know if this works or not.

VOLDADDY
08-03-2006, 11:48 PM
Well, I installed the pool coolers tonight, and I must say so far so good. My water was 91 degrees tonight, and we have nothing but 95 degree days with heat indexes of 100+ ahead. As soon as I installed them and turned my pump back on, I jumped in to see what it would do. It was amazing. The water coming out of the device was about 10 degrees cooler than the pool water. You can stick your hand in the water, then immediately put it in the water being sprayed, and it is day and night difference. I left them in and running tonight and put my Aquabot in. I also had to shock as I have some algae developing. So there is a lot of stuff going on in my pool right now. I will post back and let you know the results, hopefully getting to below 85.

CarlD
08-04-2006, 06:55 AM
I am busy trying to lower the temp on my pool, since it hit 98 yesterday!

les_smith
08-04-2006, 09:00 AM
I am busy trying to lower the temp on my pool, since it hit 98 yesterday!

Hey CarlD, I'm assuming you mean the air temperature and not the water temperature. If that's the case, I'll trade. We've been hitting 100+ for weeks now. But, we may be a little more used to it. Our pool water hit 94 and running the fountain at night (temps in the low 80s at night) has keep the pool at 90 which is doable, but not preferred. How about a 500 lb block of ice that we could swim with, wouldn't that be fun.

CarlD
08-04-2006, 10:28 AM
Nope. Last night the air was about 85 deg, 99% humidity. The pool water was 98 deg, and, of course, 100% humidity!

This morning it was down to 92/93. Yeah, the water is THAT warm!

I'm running the solar panels at night and turning them off during the day.

sailork
08-04-2006, 10:37 AM
shippy1973 I bought a second set of trippers for my intermatic timer and I run the pump twice a day. My theory is to let the extremely hot water on the surface sit there in the evening for as long as possible before I run the pump. The very hot water surface will radiate heat much faster than the cooler surface after I run the pump so I get more heat loss. On the other hand I have to mix in the bleach so I have the pump kick on at 8 or 9 and run for a few hours. One side benefit is that I find myself swimming around in the pool instead of watching TV and drinking beer.. :D

I also liked the fan idea, it's usually very still around here in the evenings. I'll have to look into that. I've got a second timer, I suppose I could put some kind of outdoor blower on it. Has anybody tried this?

VOLDADDY
08-05-2006, 04:51 PM
Well, I put the coolers on my pool Thursday night and had 91 degree water. Yesterday, it came a strong storm. Today, my pool is a brisk and wonderfully refreshing 82 degrees. I'm not sure how much can be attributed to the rain, as I know it did help, but these pool coolers do seem to work very well. If you have a problem with hot water I say give them a try. I would absolutely buy them again.

geordie
08-05-2006, 06:14 PM
I like the pool 85+ but this summer I've actually been trying to cool mine. Yesterday morning the surface temp was finally 78, but by the time I got home from work it was back up to 84. I couldn't believe it when the pool hit 92 last week (second time in six years). It doesn't feel good at all during the day, but it is kind of nice if you go out and swim late at night. Most of the last two weeks I was swimming near midnight with the pool around 90 and the air temp around 80-85. Very strange for Iowa, but I don't think I'll complain since the last two years I was struggling to keep the water above 80 much of the summer.

I take the thermometer out in the late summer when the nights start to cool (after July 29 here, normally) and the kids are used to really warm water. If my teens SEE the temp is 80 they will say it is too cold, but if they don't have the thermometer to look at they will swim down to about 77 before they mention it.