Ship fresh water circulation heat recovery system and control method thereof

The invention discloses a ship fresh water circulation heat recovery system and a control method thereof. The ship fresh water circulation heat recovery system comprises a control module, a diesel generator heating module, a diesel heater module, an air conditioner, an oil tank heating module, multiple sets of pipelines and multiple sets of valves arranged on the pipelines. The diesel generator heating module comprises a diesel generator heat exchange module and a smoke exhaust heat exchange module; fresh water flows into a diesel generator heat exchange module and/or a smoke exhaust heat exchange module in a diesel generator heating module through a pipeline to be heated, and the heated fresh water heats an air conditioner and an oil tank heating module through a pipeline. Fresh water flows back to the diesel generator heating module and/or the diesel heater module through a pipeline to be heated, and circulation is achieved. According to the heat recovery system, the water temperature of the cylinder sleeve