Diesel engine pre-heating is an essential process that keep the jacket water warm when the engine is not running or when the ship is passing through colder areas ensuring reliable engine starts, which extends the service life of the engine. Also a preheated engine consumes less fuel and releases fewer emissions, making pre-heating beneficial for the environment.

The pre-heater heats all parts of the engine, which in turn heats the air in the cylinder. This reduces cold corrosion and thermal stresses during starting. When the engine is warm, the clearances are correct, thus lubrication is made easier, and there is less chance of undue wear of moving parts.

Pre-heating also has a positive effect on the life of liquids. Liquids age quicker at extreme temperatures or extreme temperature differences. Pre-heating results in a more stable temperature, which makes the liquids last longer.

In summary, pre-heating the cooling water of a diesel engine is an essential process that ensures reliable engine starts in cold weather conditions while reducing engine wear, extending the service life of the engine. It also has a positive effect on the life of liquids and is beneficial for the environment.