Document 3QKdpMrNw9xv8wwQo3Z7BMkY6
Heating Ventilating Air Conditioning Guide 1938 388
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Chapter 19. Gravity Warm Air Furnace Systems
the Warm Air Research Residence of the National Warm Air Heating and Air Conditioning Association erected at the University of Illinois6.
Leaders. Stacks and Registers. (Direct Method) :
Living Room, 1st floor:
17,250 + 111 = 155 sq in. leader area. See summary, Table 1; also example under Standard Code7, Art. 3, Basis of Working Rules for Pipes.
Leader diameter = 14 in. Register size = 155 sq in. net area. Gross area = net area + 0.7 = 14 in. X 16 in.
Owner's Room, 2nd floor:
15,030 + 167 = 90 sq in. leader area. See summary Table 1; also example under Standard Code7, Art. 3, Basis of Working Rules for Pipes.
Leader diameter = 11.4, say 12 in.
Stack area
= 0.7 X 90 = 63 sq in. = say 5 in. X 12 in.
Register area = 90 sq in. net area. Gross area = net area + 0.7 = 12 X 12 or 12 in. X 14 in.
In like manner the leaders, stacks and registers are calculated for each room in the house.
Leaders, Stacks and Registers. (Code7 Method. See Art. 3, Sec. 1, 2, 3)
Living Room (Glass = 90, Net wall = 405, Cubic contents = 2405) .Lead.er = /^9_0 +. 4_05 +, 2w405 j9 = .1.5.5sq.n. .
Register, same as Direct Method. Owner's Room (Glass = 68, Net wall = 394, Cubic contents = 2275) tLead.er = (^_68 +, 3--94 +, 2w275 \^,,6 = ,,90sqm. .
Stack and Register, same as Direct Method.
Assuming all air recirculated, the minimum furnace for the plant will be:
Grate area = 0.0042 X 132,370 = 556 sq in. Use 27 in. diameter grate. (Equation 10).
If provision should be made for certain outside air circulation, then increase the building heat loss by, say 25 per cent and obtain by Equation
10 a 30 in. grate.
Experiments at the University of Illinois8 have shown that the capacity of a furnace may be increased nearly three times by an adequate fan,
with a constant register or delivery temperature maintained, provided that the rate of fuel consumption can he increased to provide the necessary heat. In other words, the capacity of a forced circulation system is limited by the ability of the chimney to produce a sufficient draft, and the ability of the fan to deliver an adequate amount of air.
Plans used with permission. Bathroom on third floof not heated.
7Loc. Cit. Note 3.
.
University of Illinois. Engineering Experiment Station Bulletin No..120, p. 129.
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