I want to replace my old single speed pump with a 2 speed pump, but I'm having a hard time figuring out which pump to get. any help would be appreciated.
Here are my specifics:
- Pool size: 20x40 (approx 34,500 gal)
- Plumbing: 1.5" PVC lines
- Filter: Hayward S-240 sand filter (designed flow rate 63 GPM, clean PSI - 12)
- Pump: Hayward Super Pump SP2607X10 (1 HP, 1.1 Service Factor)
- Total Dynamic Head: 35 ft (calculated using a vacuum gauge and the filter's clean PSI)
- No spa, heater, or other features
Looking at the flow vs head curves for the pump, it's operating at 60 GPM @ 35 ft of head. So it takes 9.6 hrs for one turn of the pool water.
1) This may be a stupid question, but when I look at the flow vs head curves for the 2 speed Super Pumps, they only show the curve for the low speed. I don't understand why the high speed curve is not shown?
2) If I get a 2 speed pump that operates at 60 GPM on high speed, is the low speed half of the high speed? So that would be 30 GPM? Or is that too simplistic and it depends on the head, speed, etc?
3) Any pump recommendations? I would like a manual switch to switch between high and low speeds (for vacuuming)
Thanks in advance.