248
PERFORMANCE DATA (cont)
COOLING CAPACITIES, UNITS WITH HOT GAS REHEAT OPTION (cont)
LEGEND
NOTES:
1. Direct interpolation is permissible. Do not extrapolate.
2. The following formulas may be used:
tlwb = Wet-bulb temperature corresponding to enthalpy of air leaving evapo-
rator coil (hlwb)
Where: hewb = Enthalpy of air entering evaporator coil
3. The SHC is based on 80 F edb temperature of air entering evaporator coil.
Below 80 F edb, subtract (corr factor x cfm) from SHC.
Above 80 F edb, add (corr factor x cfm) to SHC.
Interpolation is permissible.
Correction Factor = 1.10 x (1 – BF) x (edb – 80).
581A300 (25 TONS) UNIT WITH HOT GAS REHEAT IN COOLING MODE
Temp (F)
Air Entering
Condenser
(Edb)
Air Entering Evaporator — Cfm/BF
7000/0.042 8250/0.052 9500/0.062 10,750/0.072 12,000/0.082
Air Entering Evaporator — Ewb (F)
57 62 67 72 57 62 67 72 57 62 67 72 57 62 67 72 57 62 67 72
75 TC 245 268 293 318 259 282 303 333 274 291 314 340 289 301 322 348 305 309 332 356
SHC 245 229 197 162 259 254 213 173 274 271 230 183 289 287 247 195 305 298 267 203
kW 16.4 17.0 17.6 18.2 16.7 17.4 17.9 18.6 17.1 17.6 18.2 18.8 17.5 17.8 18.4 19.0 18.0 18.1 18.6 19.2
85 TC 233 259 278 309 256 273 293 324 271 282 305 330 285 290 312 337 298 303 321 343
SHC 233 228 186 158 256 252 211 171 271 264 229 180 285 276 246 191 298 295 261 201
kW 17.9 18.7 19.3 19.9 18.5 19.1 19.7 20.4 19.0 19.4 20.0 20.8 19.3 19.6 20.2 21.1 19.8 19.9 20.4 21.3
95 TC 230 252 276 303 251 265 284 314 269 274 290 326 274 282 300 332 283 293 308 334
SHC 230 225 191 156 251 249 202 166 269 269 220 181 274 274 238 190 283 280 259 197
kW 20.0 20.8 21.4 22.1 20.7 21.2 21.5 22.4 21.3 21.4 21.9 23.0 21.5 21.7 22.1 23.2 21.6 22.0 22.5 23.3
105 TC 226 245 268 292 242 253 277 301 255 264 284 308 266 275 290 314 278 281 294 319
SHC 226 223 188 153 242 241 205 163 255 255 221 171 265 265 240 185 278 278 253 194
kW 22.0 22.8 23.3 24.3 22.7 23.1 23.7 24.7 23.1 23.4 24.0 25.0 23.6 23.7 24.3 25.2 24.0 24.1 24.4 25.4
115 TC 221 233 258 281 232 242 267 290 247 253 274 297 253 260 275 302 267 269 279 306
SHC 221 217 183 149 232 230 200 160 247 246 217 170 253 254 233 179 267 267 248 189
kW 24.3 25.1 25.7 26.7 24.8 25.4 26.1 27.1 25.3 25.8 26.4 27.2 25.8 26.0 26.5 27.3 26.1 26.3 26.7 27.4
125 TC 216 223 247 268 225 230 253 275 237 240 256 280 247 248 260 285 254 255 263 288
SHC 216 212 181 145 225 223 196 155 237 236 211 163 247 247 228 174 254 254 242 184
kW 26.9 27.1 28.0 29.0 27.4 27.5 28.3 29.4 27.8 27.9 28.5 29.6 28.2 28.3 28.7 29.8 28.5 28.6 28.9 29.9
581A300 (25 TONS) UNIT WITH HOT GAS REHEAT — A IN REHEAT, B OFF
Temp (F )
Air Entering
Condenser
(Edb)
Evaporator Air Quantity — Cfm/BF
7500/0.045 8250/0.055 9500/0.065 10,750/0.075 12,000/0.085
Evaporator Air — Relative Humidity (%)
50 55 60 50 55 60 50 55 60 50 55 60 50 55 60
65 TC 79 83 87 80 84 88 81 85 89 82 86 90 83 87 91
SHC 39 33 28 41 35 30 43 37 32 45 39 34 47 41 36
kW 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11
75 TC 56 61 65 57 62 66 59 63 67 60 64 68 61 65 69
SHC 1811 52012 62215 8241610261812
kW 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11
85 TC 34 38 42 35 39 43 37 41 45 38 42 46 39 43 47
SHC –2 –11 –19 –1 –10 –18 1 –8 –16 3 –7 –14 4 –5 –13
kW 11 11 12 11 12 12 12 12 12 12 12 12 12 12 12
95 TC 12 16 19 13 17 21 15 19 22 16 20 24 17 22 25
SHC –23 –33 –42 –22 –32 –41 –20 –31 –40 –19 –30 –39 –17 –28 –38
kW 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12
581A300 (25 TONS) UNIT WITH HOT GAS REHEAT — A IN REHEAT, B ON
Temp (F )
Air Entering
Condenser
(Edb)
Evaporator Air Quantity — Cfm/BF
7500/0.045 8250/0.055 9500/0.065 10,750/0.075 12,000/0.085
Evaporator Air — Relative Humidity (%)
50 55 60 50 55 60 50 55 60 50 55 60 50 55 60
65 TC 211 222 231 215 226 235 220 232 241 226 237 247 230 242 252
SHC 123 115 109 129 121 115 139 131 124 147 139 133 155 147 140
kW 19 19 20 19 19 20 19 19 20 19 20 20 19 20 20
75 TC 182 193 202 185 196 205 189 200 210 192 204 214 196 208 218
SHC 103 93 85 110 100 91 120 110 101 128 118 110 136 126 118
kW 20 21 21 20 21 21 21 21 21 21 21 21 21 21 21
85 TC 153 164 174 155 166 176 157 169 178 159 171 181 161 173 184
SHC 84 72 62 90 78 68 100 88 78 110 97 87 118 106 95
kW 22 22 22 22 22 22 22 22 22 22 22 22 22 22 22
95 TC 124 135 145 125 136 146 125 137 147 126 138 148 127 139 149
SHC 64 50 38 71 57 45 81 67 55 91 76 64 99 85 72
kW 23 23 23 23 23 23 23 23 24 23 23 24 23 24 24
BF — Bypass Factor
Edb — Entering Dry-Bulb
Ewb — Entering Wet-Bulb
kW — Compressor Motor Power Input
ldb — Leaving Dry-Bulb
lwb — Leaving Wet-Bulb
SHC — Sensible Heat Capacity (1000 Btuh) Gross
TC — Total Capacity (1000 Btuh) Gross
tldb = tedb – sensible capacity (Btuh)
1.10 x cfm
hlwb = hewb – total capacity (Btuh)
4.5 x cfm
BYPASS
FACTOR
(BF)
ENTERING AIR DRY-BULB TEMP (F)
79 78 77 76 75 under 75
81 82 83 84 85 over 85
Correction Factor
.05 1.04 2.07 3.11 4.14 5.18 Use formula
shown below.
.10 .98 1.96 2.94 3.92 4.90
.20 .87 1.74 2.62 3.49 4.36
.30 .76 1.53 2.29 3.05 3.82