Pool heater: science question

[jeeper]

I have built a pool heater out of black plastic hose. It gets super hot after just an hour or so in the sun. I pump water into it, let it sit, then pump it out and repeat.
here is my question: would the pool warm faster doing it the way I do, or continually letting it pump through the hose?
I am adding a gallon or two of really hot water ever hour or so. But would adding a tiny bit of warmer water continually be more or less effective? Exact same?

 

[I Lean]

I think you'd warm faster by pumping continually. The colder the water in the coil, the faster it will heat. (larger temp differential) So letting it get hot sitting stagnant, you won't be fully "collecting" the sun.

Either that, or I'm wrong.

 

[Hickey]

I think you'd warm faster by pumping continually. The colder the water in the coil, the faster it will heat. (larger temp differential) So letting it get hot sitting stagnant, you won't be fully "collecting" the sun.

Either that, or I'm wrong.

I agree with this. It takes a ton of hose to warm it quickly.

 

[Jesser04]

My dad does this and he uses a sump pump and restricts the end so it’s always warm.

 

[J-mobzz]

I ran a few of the eBay solar heaters on an old pool. I just had it split off the pump so slower flow of water went through then dumped it in the pool via 1/2 hose. It was much warmer going in. The thing that I found made the biggest difference was a good cover. I bought a nice thermal (bubble wrap ) style cover and it made a really big difference

 

[jeeper]

I ran a few of the eBay solar heaters on an old pool. I just had it split off the pump so slower flow of water went through then dumped it in the pool via 1/2 hose. It was much warmer going in. The thing that I found made the biggest difference was a good cover. I bought a nice thermal (bubble wrap ) style cover and it made a really big difference

I’ve thought of these as well.. but everything on Amazon is cheap junk that falls apart. Maybe a better one from the pool supply would be good.

 

[J-mobzz]

I’ve thought of these as well.. but everything on Amazon is cheap junk that falls apart. Maybe a better one from the pool supply would be good.

I remember pulling the cover off on a few hot days and that top 6" of water being over 90deg. I think a good solar cover is worth the cost.

 

[frieed]

Before you spend a bunch of cash on a heating solution, try one of the liquid pool cover products. They work by forming a very thin layer on the surface of the water that reduces evaporation, some by up to 85%. It takes heat energy to evaporate water and that heat comes from the water itself. I used it for my pool when I lived in Texas with typical 60-70% RH air and it made a noticeable difference. I would think it would be an even more significant difference in this area with the low RH doing it's best to suck the water out of the pool.

 

[spaggyroe]

The plane takes off!!
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