What provision is made for sea chests for removal of air ingested into the sea chest of a machinery space sea water cooling system?

Correct Answer: Option B — The air may be continuously removed by an open valve located in the vent line originating from the top of the sea chest and terminating above the deep-draft load line.

Air accumulation in a sea chest can cause pump cavitation and cooling failure. A vent line connected to the highest point of the sea chest, terminating above the deep-draft load line, allows trapped air to escape continuously, ensuring the chest remains fully primed with water during all operational conditions.