Variable Speed Pump Flow Rate Approximations

The following formulas use the affinity equations to yield a very rough estimate of flow rate.

1.5" Return Line with 1 x 1.5" Suction Line:

Intelliflo Flow Rate (GPM) = RPM / 47

EcoStar Flow Rate (GPM) = RPM / 48

Plumbing Head (ft)= 0.0167 * GPM^2 - CEC Curve A

1.5" Return Line with 2 x 1.5" Suction Lines or 1 x 2" Suction Line

Intelliflo Flow Rate (GPM) = RPM / 44

EcoStar Flow Rate (GPM) = RPM / 45

Plumbing Head (ft)= 0.0140 * GPM^2

2" Return Line with 1 x 2" Suction Line

Intelliflo Flow Rate (GPM) = RPM / 37

EcoStar Flow Rate (GPM) = RPM / 38

Plumbing Head (ft)= 0.0093 * GPM^2

2" Return Line with 2 x 2" Suction Lines or 1 x 2.5" Suction Line

Intelliflo Flow Rate (GPM) = RPM / 35

EcoStar Flow Rate (GPM) = RPM / 36

Plumbing Head (ft)= 0.0083 * GPM^2 - CEC Curve C

2.5" Return Line with 1 x 2.5" Suction Line

Intelliflo Flow Rate (GPM) = RPM / 34

EcoStar Flow Rate (GPM) = RPM / 35

Plumbing Head (ft)= 0.0074 * GPM^2

2.5" Return Line with 2 x 2.5" Suction Lines

Intelliflo Flow Rate (GPM) = RPM / 33

EcoStar Flow Rate (GPM) = RPM / 34

Plumbing Head (ft)= 0.0069 * GPM^