The first step in troubleshooting involves examining the pump, the fluid and the system.
When a newly-repaired pump performs poorly, good troubleshooting procedures can help eliminate a number of possibilities—including problems with the fluid being pumped (the pumpage) or with the pipes, fittings or vessels that are connected to the pump (the system). A savvy technician with a basic understanding of pump curves and performance parameters can quickly narrow the possibilities—especially those associated with the pump.
Pump CurvesThis discussion is limited to the most common pumps in industrial and commercial applications—centrifugal pumps. The performance curves in Figure 1 illustrate how the head, flow rate, efficiency and power relate to one another for a typical centrifugal pump. As head increases, flow decreases and vice versa.
Figure 1. Head-flow pump curve: the pump curve plots normal head and flow performance and includes efficiency and power data.