GMC 1976 ZEO 6083 Maintenance Manual page 77

1- 60 AIR CONDITIONING SYSTEM
of high humidity it is possible to have thermom-
into the passenger area and resulting in insuffi
eter and gauge readings approach but not reach
cient or no cooling.
the figures listed in the performance table and
still have a satisfactory operating unit . However,
it is important to remember that low pressure
PERFORMANCE DATA
has a direct relationship to nozzle outlet temper-
ature. If pressure is too low, ice will gradually The following Performance Data define normal
form on the evaporator fins, restricting air flow operation of the system under the above conditions .
REFRIGERANT CHARGE - 3.5 LBS.
ENGINE RPM - 2000 RPM
HEAD PRESSURE (EVAP. "IN" CHARGE PORT)*
SUCTION PRESSURE
(EVAPORATOR "OUT" CHARGE PORT)*
DISCHARGE AIR TEMP . A T RIGHT UPPER OUTLET*
*Just prior to compressor clutch disengagement.
Temp. of Air
Entering Condensor 70°F 80°F 90°F 100°F 110°F
Relative Humidity (21 .1°C) (26 .7°C) (32 .2°C) (37 .8°C) (43 .3°C)
230- 270-
30% 245 285
190- 237- 283-
40% 205 252 298
157 - 202 - 242 -
60% 172 217 257
127- 167- 210-
80%
142 182 225
Temp. of Air
Entering Condensor 70°F 80°F 90°F 100°F 110°F
Relative Humidity (21 .1°C) (26.7°C) (32.2°C) (37 .8°C) (43 .3°C)
14.0- 18 .0-
30% 29.0 33 .0
11 .0-
15 .5- 20 .5-
40% 26.0 30 .5 35 .5
9.5- 13.8- 19 .0-
60% 24 .5 28.8 34.0
6 .5- 11 .0 16 .2-
80% 21 .5 26.0 31 .2
Temp . of Air
Entering Condensor 70°F 80°F 90°F 100°F 110°F
Relative Humidity (21 .1°C) (26 .7°C) (32 .2°C) (37 .8°C) (43.3°C)
60- 68-
30% 64 72
57- 65-
74-
40% 61 69 78
52- 63- 71 -
60% 56 67 75
45- 57- 65-
80% 50 61 69