What is a common indicator that there is an obstruction in the suction side of a pump?

Lower discharge head is a common indicator of an obstruction in the suction side of a pump. When there is an obstruction, it restricts the flow of water into the pump, leading to a decrease in the amount of fluid being discharged. As a result, the pressure at the discharge side drops, which is measured as a lower discharge head.

This decrease can manifest in various operational issues, including reduced performance of the pump and potential system failures if not addressed. By observing a lower discharge head, operators can infer that there might be an issue with the suction side, prompting them to investigate for possible obstructions, air leaks, or other flow restrictions.

In contrast, excessive noise, increased vibrations, and changes in oil color can also signal problems within a pump system but are not specifically direct indicators of an obstruction in the suction side. These signs may relate to other issues such as mechanical wear, misalignment, or lubrication problems, rather than flow restrictions caused by obstructions.