On most commercial cargo vessels with a relatively small crew size and few users of the potable water system, how is the potable water system pressure maintained?

Correct Answer: Option D — Cycling the potable water pump on and off by the action of the potable water hydro-pneumatic tank pressure switch in response to system demand changes.

Hydro-pneumatic tanks utilize a compressed air cushion to maintain system pressure. A pressure switch monitors this cushion; when demand drops pressure to the cut-in point, the pump starts. Once the tank reaches the cut-out pressure, the pump stops, preventing excessive cycling and maintaining steady delivery.