This chart should be used in determining what type of pump will best suit your application. The vertical dashed lines represent each model’s most efficient flow rate in gallons per minute. The curves represent the performance of each optional pump. For peak efficiency, you will want to select a pump with a performance curve that most closely matches the pressure/flow rate of your application.

For example: A 3HP Chiller comes standard with a 1/3 HP pump (curve A). At its nominal flow rate of about 7.5 gpm it can provide a system pressure of about 17 psi. If the system pressure requirement is higher, go up the dashed line to find a pump meeting that requirement.
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