Theatre Catalog (1954-55)

Recirculated aix also aids in maintaining the proper air temperature at supply outlets. For a number of different reasons, the front of the main floor of a theatre may remain cold during the heating season. A frequent cause is infiltration of air through doors located in the auditorium near the stage. Or it may result from a layer of cold air passing downward over the rear stage wall and out into the auditorium. Any attempt to warm the chilly front section of theatre seats by increasing the air temperature usually is unsuccessful. What happens is that the rear part of the auditorium becomes overheated, while the front remains cold, The best way to solve this heating difficulty is to install direct radiation near all exit doors and on the rear stage wall if it has an outside exposure. Sometimes radiation is installed in the orchestra pit to block drafts from backstage. In the summer, an overly cool front section of seats may be prevented by closing all stage doors tightly, and by determining that all vents and skylights in the stage roof are securely fastened and free from air leakage. The slightest amount of air leakage around the stage frequently is all that is required to start an objectionable and drafty forward movement of air. Automatic Controls Heart of a theatre heating system is the boiler. Firing, of course, should be automatic with gas or oil burner, or a BASEBOARD heating units keep the manager's office comfortably warm at ae circulate het boiler water under thermostatic control. all times. Baseboar Tt is easy to clean around baseboards which ‘1954-55 THEATRE CATALOG offer no obstacle to any furniture arrangement desired, besides simplifying laying of floor carpet. Stoker. This assures close control of heating costs, and eliminates arguments with the janitor over fluctuating house temperatures, the invariable result of hand-firing a boiler. Automatic temperature controls are necessary in achieving the desired degree of inside comfort during the heating Season. There should be both an inside and outside thermostat. The outside control keeps the heating system in tune with weather changes, calling for more or less heat, whichever the case may be. The inside control regulates fuel consumption to correspond to changes in the “human load.” An automatic compensating type of adjustment harmonizes and reconciles the demands of the two thermostats, enabling the heating system to maintain the exact indoor climate desired at any scason of the year, A properly-equipped boiler will have safety controls to guard against the twin hazards of overheating and excesSive pressure, besides a low water level cut-off, The steam and hot water lines of a boiler should be carefully checked for adequate size, pitch and insulation. Particular attention should be directed to any low points in the runs, which could cause objectionable noises. Typical Example The Fox Theatre in San Francisco has what may be considered a heatingcooling system typical of the larger type of film palace, The air conditioning Rr —9 Stege5 t t ‘ room occupies an entire floor nine stories above street level. Air intake shutters are under automatic control. Each of the 16 supply fans delivers 140,000 cubic feet per minute of air. Hight 14-foot main supply ducts lead from the air conditioning room to various parts of the theatre. Hach duct has a series of three steam heaters. Openings in the highly ornamental plaster-encrusted ceiling, the proscenium arch, and the organ loft distribute conditioned air throughout the auditorium. There are 414 separate openings in this theatre, each with its own damper control. The boiler room is in the basement 20 feet below sea level. A five by 20 foot tank holds the boiler’s fuel oil supply. Oil pumps are equipped with a pre-heater to bring the oil up to the point of combustion. Deep well water is pumped from the basement to the air washers by pumps operating at 1750 revolutions per minute. Air pressure on hydro-pneumatic tanks is maintained by four compressors. The centrifugal pump is one of two used to raise water from the theatre’s own deep well. x The theatre also has a reserve 6,000 gallon hydro-pneumatie air washer system. In case the regular system should break down, the auxiliary system could be used as a standby in.an. emergency for air washing, fire“\fighting, or flushing purposes. ; Included among some of the advantages of baseboard heating cre that it is clean, even, and draftless. As a matter of fact, the temperature is so even in a baseboard-heated room that there is never more than a degree or two of difference between the floor and ceiling levels. 331