Bryant 579F User Manual page 247

581A240 (20 TONS) UNIT WITH HOT GAS REHEAT — A IN REHEAT, B AND C OFF
Temp (F)
6000/0.04
Air Entering
Condenser
(Edb)
50 55
TC 73 75
65 SHC 45 42
kW 6.1 6.1
TC 55 57
75 SHC 29 25
kW 6.6 6.6
TC 38 40
85 SHC 13 8
kW 7.2 7.2
TC 20 22
95 SHC –4 –9
kW 7.7 7.7
581A240 (20 TONS) UNIT WITH HOT GAS REHEAT — A AND B IN REHEAT, C OFF
Temp (F)
6000/0.04
Air Entering
Condenser
(Edb)
50 55
TC 106 110
65 SHC 45 42
kW 10.7 10.7
TC 81 84
75 SHC 29 25
kW 11.6 11.6
TC 56 58
85 SHC 13 8
kW 12.6 12.7
TC 30 33
95 SHC –3 –9
kW 13.6 13.6
581A240 (20 TONS) UNIT WITH HOT GAS REHEAT — A AND B IN REHEAT, C ON
Temp (F)
6000/0.04
Air Entering
Condenser
(Edb)
50 55
TC 177 185
65 SHC 98 92
kW 14.5 14.6
TC 154 161
75 SHC 81 73
kW 16.1 16.1
TC 131 138
85 SHC 63 54
kW 17.7 17.7
TC 107 115
95 SHC 46 35
kW 19.3 19.3
LEGEND
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
NOTES:
1. Direct interpolation is permissible. Do not extrapolate.
2. The following formulas may be used:
sensible capacity (Btuh)
t = t –
ldb edb
1.10 x cfm
t = Wet-bulb temperature corresponding to enthalpy of air leaving evapo-
lwb
rator coil (h )
lwb
total capacity (Btuh)
h = h –
lwb ewb
4.5 x cfm
PERFORMANCE DATA (cont)
COOLING CAPACITIES, UNITS WITH HOT GAS REHEAT OPTION (cont)
7000/0.05
60 50 55
77 73 76
40 47 44
6.1 6.1 6.1
59 56 58
22 31 27
6.6 6.6 6.6
41 38 40
4 15 10
7.2 7.2 7.2
23 21 22
–14 –1 –7
7.7 7.7 7.7
7000/0.05
60 50 55
113 108 111
39 47 44
10.8 10.7 10.7
87 82 85
21 31 27
11.6 11.6 11.6
61 56 59
3 16 10
12.7 12.6 12.7
34 30 32
–14 0 –6
13.6 13.6 13.6
7000/0.05
60 50 55
191 177 185
86 100 94
14.7 14.5 14.6
168 154 162
66 83 75
16.1 16.1 16.1
145 131 139
46 66 57
17.8 17.7 17.7
122 108 115
25 50 39
19.3 19.3 19.3
Evaporator Air Quantity — Cfm/BF
8000/0.06
Evaporator Air — Relative Humidity (%)
60 50 55 60
78 74 76 79
42 49 47 44
6.1 6.1 6.1 6.1
60 56 58 60
24 33 30 26
6.6 6.6 6.6 6.6
42 39 40 42
7 17 13 9
7.2 7.2 7.2 7.2
24 21 22 24
–11 1 –4 –9
7.7 7.7 7.7 7.7
Evaporator Air Quantity — Cfm/BF
8000/0.06
Evaporator Air — Relative Humidity (%)
60 50 55 60
114 109 113 116
41 49 46 44
10.8 10.7 10.7 10.8
88 83 86 89
24 34 29 26
11.6 11.6 11.6 11.6
61 56 59 61
6 18 13 8
12.7 12.6 12.7 12.7
34 30 32 34
–12 2 –4 –10
13.6 13.6 13.6 13.6
Evaporator Air Quantity — Cfm/BF
8000/0.06
Evaporator Air — Relative Humidity (%)
60 50 55 60
192 178 186 192
88 101 95 90
14.7 14.5 14.6 14.7
169 155 162 169
69 85 78 71
16.1 16.1 16.1 16.1
145 131 139 146
49 69 60 52
17.8 17.7 17.7 17.8
122 108 116 122
29 53 42 32
19.3 19.3 19.3 19.3
Where: h = Enthalpy of air entering evaporator coil
ewb
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.
BYPASS
FACTOR
(BF)
.05
.10
.20
.30
Interpolation is permissible.
Correction Factor = 1.10 x (1 – BF) x (edb – 80).
247
9000/0.07
50 55 60 50
75 77 79 75
51 48 46 53
6.1 6.1 6.1 6.1
57 59 61 57
35 31 28 37
6.6 6.6 6.6 6.6
39 41 42 39
19 14 10 21
7.2 7.2 7.2 7.2
21 23 24 21
3 –3 –7 5
7.7 7.7 7.7 7.7
9000/0.07
50 55 60 50
110 114 117 111
51 48 46 53
10.7 10.7 10.8 10.7
83 87 89 84
36 31 28 37
11.6 11.6 11.6 11.6
57 59 62 57
20 15 10 22
12.6 12.7 12.7 12.6
30 32 34 30
4 –2 –8 6
13.6 13.6 13.6 13.6
9000/0.07
50 55 60 50
178 186 193 178
103 97 92 104
14.5 14.6 14.7 14.5
155 163 169 155
87 80 73 89
16.1 16.1 16.1 16.1
132 139 146 132
71 62 54 73
17.7 17.7 17.8 17.7
108 116 123 109
55 45 35 58
19.3 19.3 19.3 19.3
ENTERING AIR DRY-BULB TEMP (F)
79 78 77 76 75
81 82 83 84 85
Correction Factor
1.04 2.07 3.11 4.14 5.18
.98 1.96 2.94 3.92 4.90
.87 1.74 2.62 3.49 4.36
.76 1.53 2.29 3.05 3.82
10,000/0.08
55 60
78 80
50 48
6.1 6.1
59 61
33 30
6.6 6.6
41 43
16 12
7.2 7.2
23 24
–1 –6
7.7 7.7
10,000/0.08
55 60
115 118
50 47
10.7 10.8
87 90
33 30
11.6 11.6
60 62
16 12
12.7 12.7
32 34
0 –6
13.6 13.6
10,000/0.08
55 60
186 193
98 93
14.6 14.7
163 170
81 75
16.1 16.1
140 146
64 56
17.7 17.8
116 123
47 38
19.3 19.3
under 75
over 85
Use formula
shown below.