Pool cooling in muggy se missouri

[PoolDoc]

It's possible for a heat pump to cool a pool, but I don't know whether any of them are set up to do so.

Otherwise, you can run a fountain or a solar heater at NIGHT, and you'll get some cooling, but I have no idea how much.

[CarlD]

I was going to suggest a solar panel, but Ben did it first. If you install a solar panel and run it at night, it acts like a car radiator to dissipate heat. Since heat rises, it will work even if it's muggy, as long as the air is cooler than the water.

Carl

[PoolDoc]

Carl, do you know if anyone has ever done this, and reported results?

I really have no idea how well it would work . . . and the complications aren't simple.

[CarlD]

Well, I've run my panels at night when the water got too warm. But my panels are elevated, not on the ground. If your panels are directly on the ground, they bake the dirt and infuse heat into the surrounding ground that will return heat energy to the panels by conduction, but only for a while. If they are elevated you'll get less of that. Al should be up on that part.

Heat transfers in 3 ways, our old friends radiation, conduction and convection. Horizontal panels, at night, should give off heat mainly by radiation and convection. The more water you can run through them without causing it to spring leaks, the more heat will dissipate. Then turn off the feed to the panel when it's sunny. Pressure won't build up because the panel's own return remains open.

From a practical standpoint, solar panels that are close by, at ground or deck level, are really simple to plumb in. I tee off the return, with a ball valve to the panels. I have a separate return from them (actually, two returns as I split my system into two circuits after the main return).

What complications did you have in mind, Ben?

Carl

[PoolDoc]

The complication is calculating theoretical thermal loss through the things, because you have to consider things like panel emissivity, conductivity, and the sky's absorptivity (high on clear nights, low on cloudy humid ones).

When you've used yours for cooling have you ever compared influent and effluent temps. (If your pool is hot enough, a fever therm might work!)

[CarlD]

Nah...I just run 'em in the cooler night air. I've forgotten what the solar panel formula is... something like your panels should have half the surface area of your pool. 'Way more than you actually need. I have the equivalent of the 3 4'x20' panels, and the "Rule" says I'm short by one...no way! Since all you are doing is warming pool water, tight tolerances on things like panel size, flow rates, critical BTU/Calories gen'd aren't really important.

Carl