Document 82KBVz5GM2D1mwvwrG0oEM74Z

Monarch Metal Products Company Metal Weather Strips Comparison of fuel quantities and costs to heat air entering various sliding sash windows, as air infiltration or in-teakage. Assuming 65% overall efficiency of heating plant. Window, Wind, B.t.u. to raise 1 cu. ft. air from zero to 70, B.t.u. per Ih. best coal, Duration Heating Season (24 hr. per day), Cost Coal, Overall efficiency of heating plant, Net B.t.u.-- 13,080 x .65 = 8500 B.t.u. effective. Leakage-- Unstrippcd window, Monarch Rib Strip, No. 404, Monarch Adjustable Strip, No. 400, 3' x V Crack 23 iin. feet 20 miles per hour 1.439 13,080 130 days $6.00 per ton 65% (high) 114 cu. ft. per hr. per ft. crack 55.8' 24 "" "" "" "" "" . " 23 x 114 x 1.439 = 0.445 sq. ft. coal per hour 8500 0.445 x 24 x 130 2000 1385 = .694 tons per season 2000 $6.00 x .694 = $4.16 per season Unstrippcd Window "A" 23 x 55.8xl.439 = 0.218 sq. ft. coal per hour 8500 0.21.8 x 24 x 130 680 = 0.34 tons per season 2000 2000 $6.00 X .34 = $2.04 per season 23 x 24 x 1.439 = 0:0935 sq. ft. coal per hour 8500 0.0935 x 24x130 2000 0.292 = 0.146 tons per season 2000 $6.00 x 0.146 = $.875 per season Monarch Adjustable Strip No. 400 *'C Using the figures above, comparisons may be drawn between the old method of using air change and the new method of infiltration, that the air changes are dependent directly on the lineal footage of window cracks. For instance, a room having four windows would require four times as much radiation for air change as another room with a single window of the same size, irrespective of the cubical contents of the room. Heating specifications should provide, that the owner or architect guarantee the efficiency of the window to insure the satisfactory operation and low cost of a heating plant. 278 Motors and Controllers GENERAL ELECTRIC COMPANY Schenectady New York Sprague Ventilating Equipments From the early efforts at ventilating large buildings twenty years ago to the present day, the Sprague Engineers have been co-operating with archi tects and engineers in the making of practical venti lating equipment. Resulting installations are now found in many well known hotels, office buildings and department stores, where they have distin guished themselves for exceptional reliability and economnical operation. Three typical pieces of modern Sprague equipment are illustrated below: Sprague Electric controllers for varying speed A. C. fan motors with magnetic main line contractor, under-voltage and overload protection, large number of speed steps, and complete enclosure of live parts are the ideal equipment for architects and engineers to . specify when the circuit is alternating current. The Sprague type LC D. C. slow speed motor is es pecially adapted for driving ventilating fans. The steel field, laminated poles, commuttaing poles, substantial end-brackets, correct oiling systems, ideal electrical de sign, well built commuta tors, rigidly supported brush holders--these insure a long life, lowest possible current consumption and the smallest maintenance charges. Sprague Electric remote controlled push button operated, automatic self-starting speed regulators (D. C. here illustrated) for either A. C. or D. C. motors are being used to an increasing extent. These control lers are simple in operation, .with negligible up-keep expense, and control the motor, at any desired pre determined speed, from a remote point. They are destined to be adopted generally for all classes of work to supplement manually operated controllers as the standard for the future. We shall be glad to co-operate with Architects and Engineers in laying out their Ventilating Equipments. 279