Document 6eEELm946DnYxezy7Eoak8vR

942 CHAPTER 49 1949-Guide rooms for ship's personnel and offices within conditioned passenger areas. Third class staterooms are air conditioned on some ships, depending on the particular trade. Theaters, lounges, smoking rooms, beauty shops, barber shops and similar closed public spaces are usually air conditioned. All messrooms, recreation rooms, captain's and chief engineer's state rooms and offices, crew's inboard rooms and those having fixed portlights are usually air conditioned on passenger, vessels. Other living spaces are air conditioned oh some ships and only ventilated and heated on others. STATE ROOM STATE ROOM THERMOSTAT ITHCRMOSTaT V'Q HOT WATCR I \j-C A"""" | [thermostat I' HOT WATER Marine.Heating, Ventilation, Air. Conditioning 943 An important, problem in ship air conditioning concerns the treatment of the small spaces such as passenger staterooms, offices, and crew quarters. Low headroom, congested quarters, double berths, and unsymmetric^ ar rangements make each space a problem in air distribution and treatment. The simplest, system used for small spaces consists of a central filter bank, supply fan, preheater, and cooling and dehumidifying.coil. Zone reheaters are provided to take care of variations in heating loads. Control of room temperature is achieved by manual dampers, in the air supply to C- CMILteO WATER H.W-HOT WATER CLA.-0UT540C AIR CXH-EXHAUST REOR.-RCQRCULATIHC I - . ft-FiG.-1. Arrangement of Aib Conditioning System with Centbal ..... Supply Equipment and Individual Hot Wateb Room Reheatebs The treatment depends on the requirements of the operator and the pro posed itinerary of the vessel. TYPICAL COMFORT AIR CONDITIONING SYSTEMS The various types of comfort conditioning systems used to date generally have followed conventional, lines, except for those serving staterooms, offices,.and similar small spaces., Large public spaces are fitted with indi vidual systems which supply dehumidified and cooled air during the cooling; cycle and warm air during the heating cycle. In,many cases these rooms are fitted with large glass windows and doors, and require direct radiation to, offset the .downdraft.which would occur in cold weather. Finned-tube' radiation running the full length of the glass area, is commonly used for this purpose. ' Systems serving most public spaces are. designed; to provide all outside air as long as the refrigeration load is less than the capacity of the cooling equipment. Many central systems are simplified, by using 100 per cent Outside air all-year-round. the space. A recirculation-exhaust fan is provided, which'operates in-con- junction with automatic dampers to utilize the maximum quantity of out side air consistent with the capacity of-the cooling coils.' Manual speed reduction, without recirculation, is normally provided during the heating- cycle. This system' is used principally for third class, crew, arid officers' accommodations. The average total air per person is about 45 cfm| and average outside air about 15 cfm. .. A more popular system utilizes the same central supply equipment and recirculation-exhaust system as the one just described, except that'the'zone reheaters are omitted. Each space is provided with a small hot water reheater, automatically controlled by. a room ..thermostat. Heat is pro vided-through a forced circulation, single pipe,, hot water system; in most cases.;; Figr -1 shows, a.diagrammatic arrangement of this system., It should be. noted, that reheat is used to eliminate overcooling of the-indi-