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View Full Version : Two-speed pump flow rate



sharkey21
05-03-2006, 07:25 PM
Long story, but I now have a two-speed motor on my pump, and I'm trying
to determine how long I need to run it in low-speed mode to turn over the pool once (I'll put it
in high-speed mode for a couple of hours to run the Polaris, and when we want the water features on).

The motor is an A.O. Smith 2.5/0.42 HP, 11.5A/4.2A, 3450/1725 RPM. I can't find any pump
curves to tell me what GPH I'll get in low-speed mode, and even if I did, I'm
not sure what head pressure to use (the high-speed number divided by 4, I've read?).

Details: 20,000 gals, 3 scuppers, 1 fountain, Polaris on separate pump, seems
to need the 2.5HP pump to run all water features...

Any suggestions?

Thanks,

Steve

mas985
05-03-2006, 08:18 PM
Low speed mode should be about 1/2 the GPM as the high speed mode and 1/4 the head loss or filter PSI of the high speed.