What is the primary purpose of priming a pump?

The primary purpose of priming a pump is to ensure that the impeller is fully submerged in water. Priming is the process of removing air from the pump and its suction line, which allows water to fill the pump casing and enter the impeller. This is crucial because pumps cannot effectively move water when air is present; an air-filled pump will lead to cavitation, resulting in damage to the pump and reducing its efficiency.

When the impeller is submerged, it can create the necessary pressure to draw more water into the system, enabling proper operation. This is particularly important for centrifugal pumps, which rely on the presence of liquid to function correctly. Without adequate priming, the pump could run dry, leading to overheating and potential mechanical failure.

The other options do not accurately describe the primary goal of this process. Increasing motor speed, enhancing efficiency, or cooling down the mechanism might be desirable outcomes in different contexts but are not the fundamental reason for performing priming.