When should the transfer valve be set to pressure mode?

The transfer valve should be set to pressure mode when anticipating flowing less than half the capacity of the pump. This setting is crucial because it allows for better control of the discharge pressure and helps maintain a consistent pressure in the system, especially when the flow demands are lower. When operating below half the pump's capacity, setting the transfer valve to pressure mode helps prevent potential cavitation issues and ensures that the pump operates efficiently and effectively.

In this scenario, having the valve in pressure mode allows for the pump to adjust automatically to the varying flow demands while maintaining adequate pressure. This is particularly important in firefighting situations where maintaining a stable pressure is essential for effective water delivery. When flow is less than half the pump's capacity, the pressure mode helps to optimize performance and safeguard the pump from damaging conditions.