Ecotech EZ Variable Speed Motor & Hayward SuperPump (aka FrankenPump)

[mas985]

The pump must follow the affinity rules so to get the same flow rate, you need 15% more RPM. That is determined by the two different head curve's separation and there is no way around that so increasing by only 5% cannot result in the same flow rate. Unless the impellers are not what you think they are.

 

[Chuck_Davis]

Bingo!

I just referred back to the Hayward parts diagram at http://www.hayward-pool.com/pdf/Parts Diagrams/Super-Pump.pdf. I asked my local pool shop for a 1.5 HP impeller, but didn't double check the part number on what they handed me. The part they gave me is a SPX2615C, which is a 2 HP impeller.

This is actually a good thing. My impeller is only one step down from the 2.5 HP impeller and I got rid of the resonant vibration.

 

[mas985]

That makes more sense. I would expect a little less than 5% change for those two impellers. Efficiency should not change much either.

 

[astallings]

Have been using the Ecotech pump for almost a year. Usually run it at 60%. Power bill has dropped between $20 to $25 a month based on a year ago. It will pay for itself in a few more months. No ill effects as for the pool and is super quiet. Almost have to put your ear on it the hear it at 40% which is where I run it at night. Just bolted it on, connected wires, programmed it and let it rip.