Document NKQeojwqb9jb9NMpxg20p1EE

466 CHAPTER 19 1956 Guide Table 1. FirstStoey Warm Ajb Ducts* Warm Ajb Combination No. Throat Sue Leader Pipe Diameter, Inches Pipe Area Sq In Register-'Size, Inches Baseboard Size Extension Floor i 6% X 10 2 6% x 12 3 7% x 12 4 9% x 13 3db m x 12 4db 10% x 12 8 9 10 12 10 12 50 10 x 8 Wa. 8x10 64 12 x 8 u 9 x 12 78 12 x 9 334 10 x 12 113 13 x 11 5% 12 x 14 78 2(12 x 8) 2M 113 2(12 x 9) m * When the calculations indicate a requirement for a given room greater than Combination No. 4, two or more smaller units totalling the required capacity are recommended. b Double headers are permissible only where full throat areas are obtainable and room privacy is not essential. Use combination number representing total load. Combinations 3d and 4d have same capacities in Table 6 as combination 3 and 4 respectively. Table 2. Second Story Warm Air Ducts--Single Wall Stacks and Fittings Combi* nation No. Stack, Size, Inches . Leader Pipe Di ameter, Inches Pipe Area Sq In InchesRegister Size, Baseboard Floor Size Extension Sidewall u 12 14 15 16 12db 14db 10 x 3% 12 x 3% 14 x 3% 12x534 14 x 534 12 x 3% 14 x 3% 8 9 10 12 12 9 10 50 10 x 8 64 12 x 8 78 13 x 11 113 12 x 9 113 13 x 11 64 2(12 x 8) 78 2(12 x 8) 234 8 x 10 234 9 x 12 234 10 X 8 12 x 8 12 x 8 334 534 234 2(12 x 8) 234 2(12 x 8) * Recommended stack sixes. Tables may *!<> be applied to 3 in. and 3 1/2 in. stack depths. b Combinations 12-d and 14-d have same capacities in Table 7 as combinations 12 and 14 respectively. Table 3. Second Story Warm Air Ducts--Double Wall Stacks and Fittings Combi nation No. Leader Pipe Di ameter, In. Pipe Area Sq In. . Stack Size, In. Internal External 21 8 50 2J4* x 10 334* x 10% 22 8 50 3 x 10 3% x 10% 23 9 64 234* x 12 334* x 12% 24 9 64 3 x 12 3% x 12% * Commercial sizes vary 1/8 in. from values shown. Register Size, In. Floor 8 x 10 8 x 10 9 x 12 9 x 12 Baseboard Size 10 x 8 10 x 8 12 x 8 12 x 8 Ex tension 234 234 234 234 Sidewall 10 x 8 10x8 12x8 12 x 8 all correlated. Similarly in the case of return ducts, the selection specifies a complete unit consisting of return grille, return duct, and shoe connection. Recommended Standard Sizes For the purpose of simplification and standardization, selected combina tions of commercial sizes of warm air pipes, return air pipes, ducts, grilles, fittings, and registers are designated as Combination Numbers. The numbers assigned and the combinations selected as standard are fisted in the following Tables 1 to 4 inclusive.3 The selected types of fittings are shown in Fig. 2, and their resistances 6x- Gravity Warm Air Systems 467 Table 4. Return Air Ducts Combi nation No. Duct Dia. In. Duct Area Sq. In. When Joist -Space. Is Used* No. of Min.b Joists Depth Lined In. Metal Grille Srrra Choose One ABC Base-; board Intake pob First Stobt When Area at Shoe Con Duct Is Used nection, Sq. In; Choose One 31 10 78 7 8 x 14 10 x 12 32 12 113 or 2 9 5 6x 30 8x 24 12 x 14 14 x 10 4-In. Ext. 33 14 154 1 12 or 2 6 8x30 10x24 14 x 16 . 170 34 16 201- . . 1 or 2 15 ` 10x30 12x24 8; 220 35 18 254 36 20 314 2 10 12x30 14 x 24 2 12.5 14x30 18 x 24 30 x 10 4-In. Ext. ' 280 340 37 22 380 2 15.0 18x30 420 38 24 -452.^ 2 18.0 20x30 ' 500 14 x 6 12 x 8 22 x 6 16 x 8 28 x 6 22 x 8 28 x 8 22 x 10 36 x 8 28 x 10 36 x 10 30 x 12 42 x 10 36 x 12 42 x 12 36 x 14 * Based on 14 in. space between joists. b Use full depth of joist except when joist depth is less than minimum depth required, when pan mxut be need. . . . bc ^{0 F/oor Register G Fig. 2. Typical Warm Air Boots