Water and Fuel Systems Maintenance (WFSM) Set B Volume 3 Practice Test

The u-bend in the panel hydrant system pit defuel line serves a crucial function in the overall system by maintaining a portion of the line and meter from draining. This design helps ensure that there is always an adequate amount of fluid in the line, which is critical for proper operation and performance.

By keeping some fuel or fluid within the u-bend, the system prevents air from entering the line when fuel is needed, eliminating issues that could arise from a dry or empty line. This is especially important during the operation of the hydrant system, as it ensures a continuous supply and the necessary pressure for effective defueling operations.

The functionality of the u-bend contributes to system reliability and efficiency, ensuring that the components downstream can operate without interruption due to the lack of fluid, which would lead to cavitation or reduced capacity in the system.