Variable Speed Pump VS 3050---gpm/rpm?

[chem geek]

Personally, if one can afford the IntelliFlo VF pump, I'd go for it. I love mine and there is no way that I could have tuned my system as well as I did with a standard 2-speed pump. The savings I get when the solar system is on by running at 48 GPM instead of the 55 GPM with my previous fixed-speed pump is considerable while the savings I get with the solar off running at 26 GPM with the IntelliFlo compared to a 2-speed pump that might have been at around the same speed is also considerable.

If one cannot afford a variable speed/flow pump, then a 2-speed pump is still much better than single speed and will still save a lot in energy costs -- just not as much savings.

[mas985]

All true except that you really need to look at the lifetime costs of each solution and not just the energy savings. While the Intelliflo does better for energy usage, the cost premium, interface panels and/or controllers can make the 10 year cost higher for the Intelliflo than a 2 speed. So it really depends on the situation. Of course if you are only worried about carbon credits, then the Intelliflo is certainly the most ecological solution.