During a pump capacity test, if the nozzle flow is too high, what action must be taken?

In the context of conducting a pump capacity test, if the nozzle flow is too high, the appropriate action is to close the discharge gate further. This action effectively reduces the flow rate by limiting the amount of water that can exit the discharge. By closing the gate, you create more back pressure, which helps to balance the system and decrease the flow at the nozzle to the desired level.

This adjustment is made in response to the need for managing the flow rate to meet operational requirements or specifications. Striking the right balance is crucial for maintaining optimal performance, ensuring that the pump operates within the designed parameters.

The other options do not address the issue of high nozzle flow directly. Increasing the net pump pressure could exacerbate the flow issue, as it typically results in a higher discharge flow. Adjusting the water level in the tank does not directly influence the flow rate through the nozzle and might not be practical in a controlled test environment. Changing the impeller speed is a more complex adjustment that could impact the pump’s overall operation and is not a direct or immediate solution for handling high nozzle flow during a test. Hence, closing the discharge gate is the most effective and straightforward method in this scenario.