Air Requirements
A marine diesel engine needs sufficient air in order to function correctly. The volume of combustion air required is approximately 6.1m3 per kW (4.5 m3per hp) per hour, based on a maximum air velocity of 3 m/sec. In addition to combustion air, the engine also requires sufficient ventilation air to dissipate the radiated heat. The volume of ventilation air required is about the same as the combustion air needed. The design of the Vetus air suction vents is based on these principles. The Model numbers given in the table relate to the engine horsepower for which they are suitable. When designing the engine room layout, it is therefore easy to calculate the size of the air vents required. Do not forget to allow for extra air vents to extract the heat from the engine space as well. For example: a boat with an engine of 60hp will require for the combustion and ventilation air, 2 louvered air suction vents type 60 (1 x starboard + 1 x port) or 4 type 30 vents (2 x starboard + 2 x port).
This air suction vent is made of stainless steel. The synthetic rotating hose connector acts as a watertight dorade box. This vent is suitable for 16hp of engine power. Therefore for a 60hp engine, 4 of these air suction vents must be fitted (2 x to port and 2 x to starboard).