If a centrifugal pump loses water flow when throttled, what is the most accurate assumption?

When a centrifugal pump loses water flow due to throttling, a clogged strainer in the pump inlet is a likely scenario. Throttling generally refers to the manipulation of the discharge valve to control the flow rate or pressure; however, if the strainer is clogged, it creates an additional restriction at the inlet, limiting the amount of water that can enter the pump. This manifests as a drop in flow rate, making operational issues evident.

A damaged impeller could also impact flow, but this issue typically manifests in different symptoms, such as vibration or noise rather than just a loss of flow when throttling. Similarly, the length of the discharge line can affect system performance due to friction losses, but it would not typically be the immediate cause of lost flow when the pump is throttled. Low efficiency can result from various factors, but again, it wouldn’t specifically be attributed to throttling under normal operating conditions.

Overall, the presence of a clogged strainer directly impacts flow as the pump operates by limiting the water supply to the impeller, thereby making it the most accurate assumption.