Find your horsepower in the row, then read across. Total head is the lift from the pumping water level to the discharge, plus the pressure you want at the tank (2.31 ft for every PSI), plus friction in the drop pipe.
Total head in feet · curves end at 66 GPM
| HP |
0 GPM (Shut-off) |
10 GPM |
30 GPM |
50 GPM |
60 GPM |
| 1 1/2 HP |
151 ft |
143 ft |
123 ft |
91 ft |
67 ft |
| 2 HP |
180 ft |
174 ft |
149 ft |
107 ft |
78 ft |
| 3 HP |
243 ft |
242 ft |
213 ft |
156 ft |
112 ft |
| 5 HP |
423 ft |
413 ft |
366 ft |
285 ft |
218 ft |
| 7 1/2 HP |
636 ft |
616 ft |
546 ft |
428 ft |
331 ft |
Read from the published curve in the Pumps by Baker catalog (Sept 2025, rev 3/26), p. 84, digitized and rounded down, at the flows nearest 20%, 50% and 75% of the curve’s 66.3 GPM end. 0 GPM is the printed shut-off. The last column is the last flow every curve reaches; the curve ends are named in the table title.
Output in GPM at 30 PSI (switch cut-in), by depth to water
| HP |
20 ft |
30 ft |
40 ft |
50 ft |
240 ft |
260 ft |
280 ft |
| 1 1/2 HP |
— |
— |
40 |
31 |
— |
— |
— |
| 2 HP |
55 |
52.5 |
47.5 |
44 |
— |
— |
— |
| 3 HP |
66 |
62.5 |
60 |
58 |
— |
— |
— |
| 5 HP |
— |
— |
— |
— |
44 |
40 |
34 |
| 7 1/2 HP |
— |
— |
— |
— |
— |
59 |
58 |
Output in GPM at 50 PSI (switch cut-out), by depth to water
| HP |
20 ft |
30 ft |
40 ft |
50 ft |
240 ft |
260 ft |
280 ft |
| 1 1/2 HP |
17 |
12 |
— |
— |
— |
— |
— |
| 2 HP |
37.5 |
32 |
27 |
17.5 |
— |
— |
— |
| 3 HP |
55 |
52.5 |
50 |
47.5 |
— |
— |
— |
| 5 HP |
— |
— |
— |
— |
33 |
26 |
22 |
| 7 1/2 HP |
— |
— |
— |
— |
57 |
56 |
53 |
Output tables as printed in the Pumps by Baker catalog (Sept 2025, rev 3/26), pp. 83-84, at the 30 and 50 PSI rows. Riser-pipe friction is not included (manufacturer note): add it for long or small drop pipe. — marks a point A.Y. McDonald does not print for that horsepower.
Best operating range: the published curve shades the most efficient operating range for each model; the catalog prints no figures for it. The curve is in the image gallery.