Last week, I put a post on the Forum entitled ‘Upgrading single speed Super Pump to 2-speed or VS‘ but haven't got any useful response; perhaps because of a too detailed description of my issue. So, I wonder if you would kindly respond to a more direct question below.
Present situation: Present pool equipment is described in my signature (21K gal, IG plaster new 2010, 1 HP Super Pump, sand filter S-244T2, solar heating with HM-4000D controller, Hayward Cl Feeder CL220). This season, I am operating Hayward Super Pump with 1 HP single speed motor 24/7 because in the past I had to brush periodically green algae from the pool walls when operating it just 12 hrs a day.
Issue: To minimize electricity cost while providing flow rate needed for effective sanitation, I am considering a replacement of the present 1 HP single speed motor with an appropriate 2-speed motor.
Using the guidance found in Pool Pump Sizing and Super Pump performance data, I estimated the Total Head Loss and associated flow rates for Super Pump with 1 HP motor.
(a) w/o Solar heating: Total Head Loss 40 ft 54 GPM at 3450 RPM 27 GPM at 1725 RPM
(b) with Solar heating: Total Head Loss 50 ft 40 GPM at 3450 RPM 20 GPM at 1725 RPM
Based on the above, I am thinking to get from Electric Motor Warehouse a Century motor B2975T
1hp 3450/1725 230 volts 56J Pool Motor w/intergrated timer
Question: Does the above motor selection make sense? Please let me know. Thank you.