Quote Originally Posted by mas985 View Post
Your current pump should well exceed 25 GPM. More than likely your current design point is closer to 40 GPM @ 27' of head for typical AG plumbing.

Also, how do you know that the Pentair uses 10% more power and which Pentair are you talking about? Motor ratings don't really give you a realistic view of the actual power usage. Have you measured your Hayward pump's power? For typical AG plumbing, the 3/4 HP Pentair Optimo uses about 830 watts on high speed with a flow rate of about 41 GPM.
I was purely comparing faceplate numbers (8.0A for the Hayward vs 8.8A for the Pentair).

As far as all the rest goes, no I haven't measured any of it. I'm an engineer, but what I know is that what I have works, and that is good and I have no call to over-engineer it. My AG plumbing includes about an extra 100' run to and from the solar panels, which are, low side, approx 10' above the level of the pump (they are on the roof of the garage).

I've ordered a Hayward to replace the one I already have.