Heating, ventilation and air conditioning

Good ventilation is vital to the health and well-being of those on board ship and the general requirements for ventilation, formulated before the universal installation of air conditioning systems, still apply. Heating, always necessary for the colder areas of the world, has in the past been provided by local radiators or by heating coils incorporated with ventilation units. Air conditioning is based on the ventilation requirement for accommodation and incorporates heating with any necessary humidification and importantly, cooling with de-humidification as necessary. The American Society of Heating and Air Conditioning Engineers carried out a comprehensive series of tests on a large number of people, from which they were able to draw up an effective temperature chart. The accommodation is divided into zones, having different heating requirements. Separate air heaters for each zone are provided at the central unit. In winter, the air is preheated at the central unit, its temperature being automatically controlled. The air terminals are equipped with electric or hot water heating elements. It is not possible to provide ideal conditions for both heating and cooling from the same outlet. This proposal is exclusive of heating. The shipbuilder should supply and fit suitable bases for units, provide switches, wire up to motors and switches, and supply and fit cooling water drain piping and fittings.