What is critical to avoid when operating a positive displacement pump?

Operating against a closed discharge valve is critical to avoid when using a positive displacement pump because this condition can lead to a significant rise in pressure within the pump system. Positive displacement pumps work by trapping a fixed amount of fluid and moving it through the system; if the discharge line is closed, there is no place for the fluid to go, which can cause the pump to become over-pressurized. This situation can lead to mechanical failure, damage to the pump, or even safety hazards such as hose bursts or leaks in the system. Therefore, ensuring that the discharge valve is open whenever the pump is running is vital for maintaining safe and efficient operation.