If a high head pump is making a noise suggesting it is pumping rocks, what action should be taken?

When a high head pump exhibits noise indicative of potentially moving debris, such as rocks, it can signal that the pump is struggling against an obstruction or an overload condition. By restricting the discharge, the pressure in the system can be adjusted. This may relieve stress on the pump and allow it to operate more smoothly, reducing the chances of damage or further issues.

Restricting the discharge effectively changes the head conditions under which the pump operates. This may help to identify if the very issue of the noise persists due to the pump's operation or if the obstruction exists within the piping system. If the noise diminishes or disappears, it suggests the pump can handle the adjusted conditions, giving operators an opportunity to further assess the situation without immediately resorting to more drastic measures like replacement or increased speed, which could exacerbate the problem.

This approach promotes a careful examination of the issue rather than rushing to conclusions about the pump's functionality or attempting to accelerate its operation under potentially damaging conditions.