Solar pool heating pumps are "geared" differently to normal pool pumps in that they are optimized for pumping up onto a roof as opposed to high flow rate at ground level. They also include a non-return flap which is a critical component of a solar pool heating system, as it prevents pressure working of collectors up on the roof as the pump stops and water falls.

Basics of Sizing a Solar Pump

If you're installing an independent or retro/booster type system you'll need to consider solar pump sizing. If you've got an existing solar pool heating system, and need a new solar pump, we'd urge you to re-assess your pump sizing as plumbers generally oversize these pumps. You also need to consider the pressure recommendations collector manufacturers have for their systems. We always recommend running at the lowest pressure possible. An oversized pump, will not only limit collector lifetimes, but will be costly to run. An undersized pump conversely will limit collector efficiencies and not turn the water over sufficiently, resulting in poor system performance.