Document MxJnpERNgvG1O48vMDa3yvja

78 CHAPTER 5 1962 Guide And Data Book Table 12.... Selection of Bonnet Temperature, Register Temperature and Register Delivery (CFM)*"h (Far 8Uhgi Naiing a Heat lost Greater (fan 350,000 8TU/Hri Refilter Delivery Votes* fe CFM par 1000 BTU pe Hr. 10 20 30 A0 50 60 70 80 90 too no !20 ISO 140 ISO 160 170 180 190 200 2)0 220 230 240 140 14.0* 138* 136 134 132 130 128 127 126 125 124 123 121 120 119 118 117 116 115 114 113 112 111 110 109 14.4k 14.8 15.1 15.5 15.9 16.4 16.6 16.9 17.2 17.3 17.6 18-1 18.4 18.7 19.0 19;3 19.6 20.0 !ao.7 20.3 21.1 21.6 22.1 22.5 150 14S 146 143 141 139 137 135 133 131 129 128 127 126 124 123 122 120 119 118 117 116 115 114 113 12.6 12.8 13.1 13.5 13.9 14.2 14.6 14.9 15.3 15-7 16.2 16.4 16.6 16.9 17.3 17.6 17.9 18.4 18.7 19.0 19.3 19.6 20.0 20.3 20.7 . 160 15S 155 152 150 147 145 143 140 138 136 134 132 130 128 127 126 125 124 123 121 120 119 118 117 11.4 11.6 12.0 12.3 12.6 12.9 13.2 13.5 14.0 14.4 14.8 15.1 15.5 15.9 16.4 16.6 16.9 17.2 17.3 17.6 18.1 18.4 18.7 19.0 19.3 170 167 164 161 158 155 152 150 147 145 143 140 138 136 134 132 130 128 127 126 125 124 123 121 120 10.5 10-7 11.0 11.3 11.6 12.0 12.3 12.6 12.9 13.2 13.5 14.0 14.4 14.8 15.1 15.5 15.9 16.4 16.6 16.9 17.2 17.3 17.6 18.1 18.4 180 177 173 170 167 164 161 158 155 152 150 147 145 143 140 138 136 134 132 130 128 127 128 124 9.7 9;9 10.2 10.5 10.7 11.0 11.3 11.6 12.0 12.3 12.6 12.9 13.2 13.5 14.0 14.4 14.8 15.1 15.5 15.9 16.4 16.6 16.9 17.2 17.3 190 186 182 178 175 172 168 165 162 159 156 153 151 148 146 143 141 139 137 135 133 131 129 128 127 9.1 9.3 9.6 9.8 10.0 10.3 10.7 10.9 11.2 11.5 11.8 12.2 12.4 12.8 13.1 13.5 13.9 14.2 14.6 14.9 15.3 15.7 16.2 16.4 16.6 200 196 191 187 183 179 176 172 169 166 163 160 157 154 151 149 147 144 142 140 138 135 133 131 130 8.6 8.8 9.0 9.3 9.5 9.8 9.9 10.3 10-6 10.8 11-1 11.4 11.7 12.1 12.4 12.7 12.9 13.4 13.7 14.0 14.4 14.9 15.3 15.7 15.9 Register temperature, Fahrenheit. (Um upper value in each group.) k Register delivery volume in cubic feet per minute per 1000 Bta. (Use lower mine in each group.) * Bsgister delivtry wlimt is colamp 1 ere for aero length of duct. (such aa Fig. 2 or Fig. 3, Chapter 12 of the 1961 Guide And Data Book), volume (cfm), and pres sure drop per 100 ft of duct. B. Return air branches. a. Select a low value of actual duct loss obtained from step b under item A for the suction loss of return duct system. b. Proceed' in siting return air branches by the name method described for the warm air branches. C. Trunk ducts for warm air and return air sides ofsystem. a. Add air volumes of branches to be handled by each trunk duct. b. The friction loss per 100 ft of trunk duct is deter mined by taking the smaller of the two values for friction foes for the two ducts meeting at the junc tion. c. 'Determine trunk duct sise by using an air friction chart, volume (cfm), and pressure drop per 100 ft of trank duct. 8- Selection of Blower. A. Determine total cfm air delivery (the sum of all branch cfm values). B. Determine static pressure requirement. a. For furnace-blower combination units it is the sum of bonnet pressure and suction pressure. b. For blowers separately selected from the furnace it is the sum oi bonnet pressure, suction pressure, filter loss, casing loss, losses through air washers, coils, and other devices. 9. Selection of Furnace. A. Determine register delivery (the sum of room Bta losses). B. Determine bonnet capacity. If the ductwork is all lo cated in spaces that have been included in the calcu lated heat loss, the required bonnet capacity can be considered equal to the required Btuh register deliv ery. If the furnace and ductwork are located in spaces not included in the heat loss, the required bonnet capacity of the furnace can be determined from: Btuh = (cfm) X (temperature rise) X (1.08) C. Determine allowance for pick-up load. For buildings which are heated intermittently, such aa churches and auditoriums, it is customary to add from 10 to 25 per cent extra furnace capacity for warming of the struc ture. The design procedure outlined above results in a duct system which has been described as a trunk-and-branch system. A trunk duct may or may not be reduced in size as each branch duct leaves the trunk. If the trunk duct is not reduced as each branch duct leaves the trunk duct, the trunk duct take-off fittings designated as EP1 to EP4 in Fig. 7 are used. The air velocity within a uniformly sized trunk duct decreases as air leaves it through the branch ducts. It is therefore desirable to reduce the trunk duct size frequently enough that the air velocity within it does not drop below about 350 fpm. The simplified procedures which have been outlined are based upon an assumed air temperature of 70 F surrounding Worm Air Heating Systems 79 Toble 13 .... Determination of Free Area and Total Pressure Loss of Register for 22 Deg Deflection of Air** * * Register Free Area in Square Inches (Upper vela* in eod groapl Pressure lou io ladies of Water (lower rates in each group) ResdentioJ Use Residential Use Distance tree Register to Opposite WaO 'rrCte Reg. Size or fqpirataaf Cfm Reg. Size or Equivalent Pressure loss Cta 31-34 35-3? JiO-49 50-59 60-69 70-79 80-69 A' 1 Up to 59. 10 x 4 10 x 6 .01 .01 100-119 12 x 6 14x4 .02 .02 700-739 . 243 0.02 186 0.03 127 0.06 85 0.11 60-69 10x6 12 x 4 .01 .02 120-129 12 x 6 24 x 6 .02 .02 740-779 271 208 141 94 0.02 0.03 0.05 0.10 70-99 * 10x8 12x6 .02 .02 130-169 14x6 .02 780-819 230 157 105 0.02 0.05 0.09 170-189 14 x 8 .02 820-859 Distance From Register to Opposite Wa0 254 173 115 0.02 0.04 0.08 Cfm 190-209 Up to 18 19-21 2224 2527 2B-3Gj 31-34 35-39 40-49 50-59 860-899 A 68 49 38 29 24 19 0.02 0.03 0.05 0.08 0.11 0.16 900-930 278 190 126 0.02 0.04 0.08 304 207 138 0.02 0.04 0-07 210-229 82 60 45 35 28 23 0.02 0.03 0.04 0.06 0.10 0.13 940-979 332 226 151 108 0.02 0.03 0.07 0.12 230-249 71 54 42 34 28 22 0.02 0.04 0.06 0.08 0.11 0.17 980-1019 360 245 163 118 0.02 0.03 0.06 0.11 250-269 84 63 49 40 32 25 0.02 0.03 0.05 0.07 0.10 0.16 1020-1059 390 265 177 127 0.02 0.03 0.06 0.11 270-299 100 76 60 48 38 30 0.02 0.03 0.04 0.06 0.09 0.13 1060-1099 285 190 137 0.03 0.06 0.10 300-339 96 73 60 48 37 0.02 0.04 0.05 0.07 0.11 1100-1139 307 204 147 0.03 0.05 0.09 340-379 122 95 78 61 47 33 0.02 0.03 0.04 0.06 0.09 0.18 1140-1179 330 220 158 0.02 0.05 0.09 380-419 117 94 75 58 39 0.02 41.03 0.05 0.08 0.15 1180-1219 353 235 169 0-02 0.04 0.08 420-459 142 113 91 70 47 0.02 0.03 0.04 0.06 0.13 1220-1259 376 251 180 0.02 0.04 0.08 460-499 168 135 108 83 56 0.02 0.03 0.04 0.06 0.11 1260-1299 401 267 192 136 0.02 0.04 0.07 0.13 500-539 159 126 97 66 0.02 0.03 0.05 0.10 1300-1339 426 284 204' 144 0.02 0.04 0.07 0.13 540-579 580-619 62(0659 660-699 185 147 113 '77 0.02 0.03 0.04 0.08 1340-1379 212 0.02 169 0.03 192' 0.02 130 0.04 147 0.03 88 0.08 100 0.07 51 0.18 1380-1419 59 0.15 1420-1459 217 166 0.02 0.03 113 0.06 75 0.13 1460-1500 452 301 217 154 109 0.02 0.04 0.06 0.12 0.22 479 319 230 163 116 0.02 0.04 0.06 0.12 0.21 508 338 244 172 122 0.02 0.03 0.06 0.11 0.20 536 356 256 182 129 0.02 0.03 0.06 0.10 0.19 * Total pressure (itetis plus velority) loee is baaed oa FLAT FACE ADJUSTABLE BAB TYPE and doee NOTiociude stockhead. , Talara ob the right erf line A and A' should not be need in applications such aa eburebra. auditoriums, sad oooccrt holla. Valots oa right erf line B end B' should not be aged in applications such as residential work, motion picture tbeaten, court rooms, and schnola. Fr floor and baseboard registers where a velocity of approximately 100 FPM is used. the free --- - CFM X U4-------------;--*->- ^?M of OAL