According to the illustrated main engine cooling water systems diagram, which of the following heat exchangers would be isolated and bypassed while maneuvering in or out of port? Illustration MO-0111

Correct Answer: Option D — 23 and 24

Auxiliary coolers such as central sea-water-cooled units 23 and 24 are isolated and bypassed during maneuvering to handle reduced thermal loads and prevent over-cooling of machinery when operating at low speeds in port waters.