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American Society of Heating and Ventilating Engineers Guide, 1928 No additi'onal^allowance need be made for covered mains or risers, but exposed mains or risers used as heating surfaces should be included in calculating the equivalent square feet of direct, radiation. PUMP SPECIFICATIONS Reciprocating and power driven pumps should be specified as to make, size, water and steam working pressures, piston speed, temperature of water to be handled, electric motor characteristics, etc. Table 15. Motor Driven Condensation Pump Capacities for Delivering Against Various Pressures Radia tion in Sq. Ft. of Direct Radia tion Minimum Gallons per Min. Maximum Boiler Motor Pressure H. P. Lb. 4000 4000 4000 6-8 6-8 6-8 10 15-40 50-60 34 34 34 6000 6000 6000 9-12 9-12 9-12 10 15-40 50-60 y* 34 1 8000 8000 8000 8000 10,000 10,000 10,000 10,000 10,000 12-16 12-16 12-16 12-16 15-20 15-20 15-20 15-20 15-20 10 15 20 30-60 10 15 20-30 3040 50-60 34 34 1 m 34 34 l m 2 Sug gested Size of Piping Inches i i i m IX 134 m m 134 m 134 134 134 134 134 Radia tion IN Sq. Ft. of Direct Radia tion Minimum Gallons per Min. Maximum Boiler Motor Pressure H. P. Lb. 15,000 15,000 15,000 15,000 15,000 20,000 20,000 20,000 20,000 20,000 25,000 25,000 25,000 25,000 25,000 30,000 30,000 30,000 30,000 25-30 25-30 25-30 25-30 25-30 30-40 30-40 30-40 30-40 30-40 40-50 40-50 40-50 40-50 40-50 50-60 50-60 50-60 50-60 10 15 20-30 40 50-60 10 15 20 3040 50-60 10 15 20 3040 50-60 10 15 20 30-60 34 1 134 2 3 3A 1 2 3 5 1 134 2 3 5 1 134 2 5 Sug gested Size of Piping Inches 2 2 2 2 2 2 2 2 2 2 234 234 2J4 234 234 - 234 2J4 234 234 The kind of drive should be specified for power driven pumps. Centrifugal and rotary pumps should be specified as to make, type, capacity, temperature of water to be handled, speed and motor charac teristics including: % (1) Name of motor manufacturer; (2) Manufacturers rated Horse Power; (3) The maximum temperature rise for any part of the motor above the temperature of the surrounding air; (4) Full Speed in R. P. M; (5) Current characteristics; (6) Whether the motor is open, semi-enclosed or fully enclosed. The following should also be included in the specifications, total head to be pumped against including suction lift, friction head, velocity head and head against which the pump must discharge. The vacuum under which return pumps are required to operate and as to whether two or more units are to operate in parallel or separately. All pumps should be set on substantial foundations and be provided with heavy cast iron sub-bases, securely anchored to foundation and pro vided with drip ring with drain properly connected to sump or sewer. 190 Chapter IX--Pumps for Heating and Ventilating Equipment Table 16. One Pump One Motor Return Line System Size A B C D E F G H Sq. Ft. Direct Equivalent radiation Surface Diameter Orifice Vacuum 10 In. 8000 16,000 26,000 40,000 65,000 100,000 150,000 250,000 9-64 3-16 1-4 9-32 3-8 1-2 9-16 Three 1-2 Air Capacity Cu. Ft. per Min. 6 11 19 25 42 75 90 180 Water Capacity Gals, per Min. 10 Lb. Pres sure 180 F. ii 22 35 60 90 140 200 400 Actual H. P. 0.9 1.4 2.0 2.8 3.9 9.0 10.0 10.0 R. P. M. H. P. of Motor 1800 ' 1800 1800 1200 1200 1200 900 720 i 134 2 3 5 10 10 20 Table 17. Two Pump One Motor Return Line System Vacuum Pumps Capacity Sq. Ft. of Direct Radiation 6000 6000 8000 8000 12,000 12,000 18,000 18,000 30,000 30,000 Capacity G. P. M. 9 9 12 12 18 18 27 27 45 45 Pressure at Pump 10 15 10 15 10 15 10 15 10 15 Motor H. P. 34 l l 134 l 134 134 2. 2 3 Table 18. Two Pump Two Motor Return Line System Vacuum Pump Capacity Sq. Ft. OF Direct Radiation Capacity G. P. M. Pressure at Pump 6000 6000 8000 8000 12,000 12,000 18,000 18,000 25,000 25,000 30,000 30,000 9 9 12 12 18 18 27 27 38 ' 38 45 45 10 15 10 15 10 15 10 : 15 . 10 15 10 15 Motor H. P. Air Water 34 34 34 34 34 34 34 34 1 l l 1 34 34 34 l 34 l l 2 134 2 134 2 The exhaust from steam driven pumps supplying steam for heating purposes should be taken through an efficient oil separator before entering any part of the heating system or other apparatus. Motors should be not less than Yi greater in horsepower than that actually required to drive the pump under full load conditions. 191 x