What should be done if the anticipated GPM exceeds half the pump's capacity?

When the anticipated gallons per minute (GPM) exceeds half the pump's capacity, setting the transfer valve to Volume mode is the appropriate action. In Volume mode, the pump operates in a manner that allows for maximum flow rates without compromising pressure, which is essential in situations where high GPM is required. This setting ensures that the pump can handle the increased water flow efficiently by drawing from the water source without overloading or straining the system.

In contrast, reducing engine speed may adversely affect the pump's ability to maintain sufficient pressure and flow. Closing the tank fill valve can restrict the water supply, leading to insufficient flow. Adjusting the discharge pressure might be necessary in some scenarios, but it does not directly address the issue of exceeding half the pump's capacity and may lead to unintended pressure losses or issues. Therefore, setting the transfer valve to Volume mode is the most effective strategy to manage high flow demands safely and efficiently.