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1952 Theatre Catalog, 10th Edition, Page 30 (xxx)

1952 Theatre Catalog, 10th Edition
1952 Theatre Catalog
1952 Theatre Catalog, 10th Edition, Page 30
Page 30

1952 Theatre Catalog, 10th Edition, Page 30


' Radiators

Radiators are unsightly and often inefficient. If air conditioning with indirect heating coils is to be installed, old cast iron radiators along the side walls of the auditorium may be eliminated. Where outmoded radiation is required, the clumsy iron radiators can be supplanted by fin-type radiation enclosed in recessed convectors, thus saving space and making a definite improvement in the theatre's appearance. The installas tion of a booster heating coil and blower to direct heated air across the front entrance doors will greatly aid in elimie nating cold drafts in the lobby and at the rear rOWS of seats.


The old boiler should be checked carefully for cracked sections if it is to be retained. The tubes and shell must be examined if the boiler is of the cast iron sectional type or of the steel tubular type. A standard type of boiler covering should be used to insulate both types, and thorough patching and renewing should be done where needed. If automatic high-low water cutoffs are not part of the old boiler equipment,


If the theatreis heating plant is to be replaced, a number of considerations will govern the selection of the new unit, and these will be touched upon in this section. If it is decided to retain the old heating plant, the chances are it will require extensive overhauling to put it in condition to operate economically and efficiently.

these should be added. Steam or hot water supply lines and return lines should be examined for size, pitch, covering and possible low points in the runs which are the cause of circulation stoppage and annoying noises.

If the boiler is in safe, efficient operating condition, but is hand-fired, it might be advantageous to install a mechanical firing unit, either a stokcr, oil burner or gas burner. The gas burner is the most convenient of the three but would be the most economical only in areas where natural gas is available at low rates. Availability of fuel and its cost will also govern the choice of a stoker or oil burner.

Automatic Controls

Automatic controls, actuated by thermostats located throughout the theatre and outside the theatre, should be installed regardless of the type of fuel used. These controls will make possible the variation of the amount of fuel consumption with the variation of the human load inside the theatre, and will anticipate a change in the outside temperature, thereby conserving fuel and maintaining comfortable temperatures in the theatre at all times.

It will sometimes be found that the replacement of direct radiation with indirect heating will be leSS expensive


than putting in new supply and return lines under the floor slab, if the old lines are in poor condition. If a new air-conditioning system is to be installed during remodeling, this would be considered in the change of heating systems as an indirect heating system will necessarily depend on a blower for circulation of the heated air, and direct radiation will have to be retained in the front of the house, including the toilet rooms, projection booth and other parts of the building.


Duct Installation

When ducts are installed over a ceiling, extreme care must be taken to avoid ceiling damage, and workmen must be impressed with this fact before any work begins. Temporary plank walkways should be installed in the work space, and continual inspections should be conducted while the work is in progress and afterward to make sure that no plaster bond has been broken and that no hanging supports have been severed without proper replacement or reinforcement.

Damage will be difficult to detect from above as well as from the orchestra or balcony, and the plaster ceiling may be so weakened by unapparent damage as to become a serious threat to the safety of the patrons below. This is especially applicable if the ceiling has heavy ornamentation.

While it is possible to allow much of the work required for an air conditioning sysem or ventilating system to proceed while the show is running, it is dangerous to have work proceeding above the ceiling during show time.

The problem of distributing air properly in the auditorium becomes more difficult in cases where there is no space in the attic for ducts. Large ducts sometimes can be run over the rooftop, in which case they will have to be well insulated. Ducts also can be disguised as beams, and run through the center and directly under the ceiling or along the sidewalls. Where duct sizes are smaller, in other sections of the house, ducts can be furred in so that they do not mar the general appearance.

If it is decided to retain existing metal ductwork, duct interiors will have to be cleaned of thick layers of accumulated dust and dirt. Many contractors specialize in this type of work, and do a highly satisfactory job of cleaning, using Special vacuum equipment.

In installing a new air-conditioning system, the ducts required to circulate the air may pose a serious problenu However, if trusses have been used in the construction of the roof, the problem is partially solved as there will then be sufhcient space above the ceiling of the auditorium to run the larger ducts.

While ducts are being cleaned, the entire duct system should get a complete going-over. All joints and scams which may have come open should be secure ly sealed in place. Loose or missing hangers should be repaired or replaced. Particular attention should be given to points where sheet metal ducts join with ducts of masonry or plaster.

The plenum spaces, to which ducts are connected, will require similar cleaning and servicing. Quite often the space between the balcony soffit or that of the mezzanine are used for this purpose, and the duct connections here should be cleaned and secured. Such servicing often will spell the difference between poor operation of the air circulating sysem and good operation. Once the entire system has been put in good condition, periodic inspections should be scheduled to insure against future breakdowns.

Excessive accumulation of dirt in the plenum spaces indicates leakage or the need for new filters. Some ventilating systems were not installed with filters, and where this is the case the installation of them will greatly aid in keeping the theatre clean. Disposable filters of glass fibre, animal hair and other materials are the least expensive and are most satisfactory, provided they are inspected regularly and replaced when no longer effectvie. Better results, at higher cost, can be attained with automatic self-cleaning filter equipment.

If in the course of the duct system inspection it is found that rust deposits have formed, excessive condensation is taking place because of the difference in the temperatures of the air in the duct and the air in the enclosing space. This usually occurs where main supply ducts run over suspended ceilings, and the attic space becomes very hot due to the lack of r00f insulation and proper ventilation of the attic space. This condition may be relieved considerably by gravity ventilators through the roof into this space, with louvers in the outside walls at each corner to provide circulae tion. Ventilators and louvers should be equipped with weather-proof closures. In addition, it may be necessary to insulate the ducts themselves. This will not only put an end to condensation, but will take a large load off the air conditioning system.

If new roofing is to be installed, it is recommended that the required insulation be installed on the roof deck before the new roofing is put on, thus ruling out the necessity of insulating the ducts. However, gravity ventilation should be provided for regardless of whether the roof is insulated.

Before fans or other heavy equipment is located in any part of the building, structural supports should be checked by an experienced engineer, and additional supports or reinforcing that may be needed to carry additional loads should be installed. Special caution is required in this regard where equipment is to be installed on the roof. Fans and compressors must not be placed where their noise or vibrations can possibly interfere with the show, and should be mounted on heavy concrete foundations and equipped with vibration eliminators. The sound of rushing air may be eliminated by setting the large supply fan to run at a low velocity. If the gas piping from the compressor to the condenser is attached to a structural mem THEATRE CATALOG 1952
1952 Theatre Catalog, 10th Edition, Page 30