Solar Thermal Based Swimming Pool Heating System
Low pressure is the bottom line when it comes to setting solar up for long term reliability. You can't expect a thin plastic collector to withstand extreme temperatures, thermal movement, aging etc all in combination with stress from pressure in the water. Take away the pressure and you compromise NOTHING. You simply allow the system to operate stress free the way it is intended and you've removed the source for problems. We end up solving other problems in this process and creating a harmonious smooth operating pool mechanical system. Easy to say. Not nearly as simple as you might think to accomplish.
This is our most common solar design for a simple pool without a spa and without "in-floor" cleaning built in where the collectors are elevated up at least one storey. This design requires that the pressure where solar ties in is low.
All products of this style (water flows up the collectors not horizontally and there are about 100-200 flow cores per 4' wide collector) perform exactly the same because they are all the same color and temperature (black and cold) and that's all there is to a comparative efficiency test in this industry. We don't need glass over the collectors because the air is warm relative to collector temperature. If you're comparing collectors based on performance ratings published by an accredited testing agency you're looking at the wrong features. If set up properly we can make any of the 20 collectors manufactured in the US operate almost exactly the same, at top efficiency.
Through extensive collaboration with universities and gov't we've learned to simulate the performance of a solar pool heater with remarkable accuracy. We've verified these curves repeatedly with real systems and found excellent correlation. Below is is a typical pool in San Diego CA with a little pool shade, located near the ocean where the collectors are on a south facing roof.