Lennox ELITE 12GCS Series Unit Information page 18

B−12GCS
For maximum performance of this cooling system, the
operating temperatures and pressure should be checked
and superheat determined at Standard ARI test conditions
of 82_ F outdoor temperature − 80_F indoor dry bulb / 67_F
indoor wet bulb. If superheat measured deviates from
values in table 9, refrigerant charge should be adjusted
accordingly for maximum performance.
80°F db / 67°F wb RETURN AIR
MODEL PRESSURE
12GCS−024
12GCS−030
12GCS−036
SUCTION SUCTION
12GCS−042
12GCS−048
12GCS−060
12GCS−024
12GCS−030
12GCS−036
LIQUID LIQUID
12GCS−042
12GCS−048
12GCS−060
TABLE 9
12GCS SUCTION SUPERHEAT TABLE
UNIT MODEL NO.
12GCS−024
12GCS−030
12GCS−036
12GCS−042
12GCS−048, −060
TABLE 10
NORMAL OPERATING PRESSURES
AIR TEMPERATURE ENTERING OUTDOOR COIL (°F)
65° 70° 75° 80°
75 77 80 82
67 70 73 76
73 75 78 80
77 78 80 81
71 74 75 79
74 77 80 81
149 164 178 193
145 161 178 192
156 172 187 203
159 175 190 208
152 168 185 198
155 190 205 211
Page 18
Verify system performance using table 10 as a general
guide. Table should not be used for charging unit. Minor
variations in these pressures may be expected due to differ-
ences in installations. Significant differences could mean
that the system is not properly charged or that a problem ex-
ists with some component in the system. Used carefully,
this table could serve as a useful service guide. Data in
table 10 is based on 80°F dry bulb / 87°F wet bulb return air.
Allow unit operation to stabilize before taking pressure
readings.
SUCTION SUPERHEAT
82_F OD − 80_F IDDB
/ 67_F IDWB
18 − 20_
18 − 20_
13 − 15_
13 − 15_
14 − 16_
82° 85° 90° 95°
83 84 87 88
80 78 82 85
82 82 85 87
81 82 84 85
81 81 84 88
82 84 85 88
195 208 222 237
195 207 223 238
207 219 234 260
209 222 237 253
209 215 230 246
215 230 244 269
100° 105° 110° 115°
90 90 91 92
86 86 87 88
88 89 91 92
87 88 89 90
87 87 88 89
96 96 87 88
254 271 289 306
254 270 288 305
267 284 303 322
270 298 306 326
254 281 298 316
276 293 311 332