A bulk carrier was entering ice-infested waters. In preparation, the engineering staff completed an ice navigation checklist and, among other things, opened the steam valve to the lower sea chest as they thought this would prevent ice build-up.
During the night, the electrical officer of the watch (EOW) noticed a rise in temperature in the fresh water cooling system. He called the chief engineer, who attributed the rise in temperature to an ice blockage in the low sea chest suction. Arrangements were made to use water from the forepeak ballast tank to lower the cooling water temperature.
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