Generally, the requirements for engine room temperature of ships are not too high. What matters is the inlet temperature of the main engine and auxiliary engine. Because the heat of main engine and auxiliary engine is relatively high, if the inlet air temperature is high, the exhaust temperature will also rise, which will affect the economic performance of diesel engine. Generally, there are several fans on board, so it is enough to keep the engine room at about 40 degrees through circulation. In addition, in general, the temperature in the oil separator room will be higher because it is heated by fuel vapor.