Bryant 581A Gas Heater User Manual


 
186
PERFORMANCE DATA — 579F (cont)
COOLING CAPACITIES (cont)
LEGEND
NOTES:
1. Direct interpolation is permissible. Do not extrapolate.
2. The following formulas may be used:
Where: h
ewb
= 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).
579F216 (18 Tons) (cont)
Temp (F)
Air Entering
Condenser
(Edb)
Evaporator Air Quantity — Cfm
9000
Evaporator Air — Ewb (F)/BF
54/0.65 58/0.53 62/0.40 67/0.25 72/0.23 76/0.23 80/0.05
75
TC 223 223 228 239 258 275
SHC 223 223 202 181 144 113
kW 14.3 14.3 14.4 14.6 15.0 15.4
85
TC 216 217 222 231 250 266
SHC 216 217 194 177 141 110
kW 15.8 15.9 16.0 16.3 16.7 17.1
95
TC 210 210 215 223 241 257
SHC 210 210 187 174 138 107
kW 17.6 17.6 17.7 18.0 18.4 18.8
105
TC 202 202 207 214 231
SHC 202 202 184 170 134
kW 19.4 19.4 19.5 19.7 20.2
115
TC 195 195 196 204 221
SHC 195 195 192 166 131
kW 21.3 21.3 21.4 21.7 22.2
117
TC 193 193 194 202 219
SHC 193 193 192 166 130
kW 21.7 21.7 21.7 22.0 22.6
120
TC 191 191 191 199
SHC 191 191 191 164
kW 22.3 22.3 22.3 22.6
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
t
ldb
=t
edb
sensible capacity (Btuh)
1.10 x cfm
t
lwb
=
Wet-bulb temperature corresponding to enthalpy of air
leaving evaporator coil (h
lwb
)
h
lwb
=h
ewb
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
0.05 1.04 2.07 3.11 4.14 5.18
Use formula
shown below.
0.10 0.98 1.96 2.94 3.92 4.91
0.20 0.87 1.74 2.62 3.49 4.36
0.30 0.76 1.53 2.29 3.05 3.82
0.40 0.65 1.31 1.96 2.62 3.27
0.50 0.55 1.09 1.64 2.18 2.73
0.60 0.44 0.87 1.31 1.74 2.18
0.70 0.33 0.65 0.98 1.31 1.64