INDOOR AIRFLOW AND AIRFLOW ADJUSTMENTS
For heating and cooling operation, the recommended airflow
is 350 to 450 cfm for each 12,000 Btuh of rated cooling
capacity. for units with optional electric heat, the airflow must
not be reduced below the levels stated in Tables 2A and 2B.
Tables 4A and 4B shows both heating and cooling airflows at
various external static pressures. Refer to these tables to determine
the airflow for the system being installed.
NOTE: Be sure that all supply-and return-air grilles are open, free
from obstructions, and adjusted properly.
Airflow can be changed by changing the lead connection of the
blower motor.
Unit 50JS and JX three-speed motors (except sizes JS 018 and JX
030) are factory wired for low speed operation. Unit 50JX 030 is
factory wired for medium speed. Unit 50JS 018 has a two-speed
motor wired for low speed.
For 208/230-v Motors:—The motor leads are color-coded as
follows:
3-SPEED
Black = high speed
Blue = medium speed
Red = low speed
Fig. 23—Cooling Charging Chart, 50JS 018 Units
C00026
SUCTION LINE PRESSURE (KILOPASCALS)
SUCTION LINE PRESSURE (PSIG)
-7 -1 4 10 16 21 27
SUCTION LINE TEMPERATURE (°F)
SUCTION LINE TEMPERATURE (°C)
689
620
551
483
414
345
276
207
100
90
80
70
60
50
40
30
(018) 60HZ CHARGING CHART
20.0 30.0 40.0 50.0 60.0 70.0 80.0
OUTDOOR TEMP
° F ° C
115 46
125 52
45 7
55 13
65 18
75 24
95 35
105 41
85 29
50JS500087
Fig. 24—Cooling Charging Chart, 50JS 024 Units
C00027
SUCTION LINE PRESSURE (KILOPASCALS)
SUCTION LINE PRESSURE (PSIG)
-7 -1 4 10 16 21 27
SUCTION LINE TEMPERATURE (°F)
SUCTION LINE TEMPERATURE (°C)
758
689
620
551
483
414
345
276
110
100
90
80
70
60
50
40
(024) 60HZ CHARGING CHART
20.0 30.0 40.0 50.0 60.0 70.0 80.0
OUTDOOR TEMP
° F ° C
115 46
125 52
45 7
55 13
65 18
75 24
95 35
105 41
85 29
50JS500088
Fig. 25—Cooling Charging Chart, 50JS030 Units
C00028
SUCTION LINE PRESSURE (KILOPASCALS)
SUCTION LINE PRESSURE (PSIG)
-7 -1 4 10 16 21 27
SUCTION LINE TEMPERATURE (°F)
SUCTION LINE TEMPERATURE (°C)
689
620
551
483
414
345
276
207
100
90
80
70
60
50
40
30
(030) 60HZ CHARGING CHART
20.0 30.0 40.0 50.0 60.0 70.0 80.0
OUTDOOR TEMP
° F ° C
115 46
125 52
45 7
55 13
65 18
75 24
95 35
105 41
85 29
50JS500089
Fig. 26—Cooling Charging Chart, 50JS 036 Units
C00029
SUCTION LINE PRESSURE (KILOPASCALS)
SUCTION LINE PRESSURE (PSIG)
-7 -1 4 10 16 21 27
SUCTION LINE TEMPERATURE (°F)
SUCTION LINE TEMPERATURE (°C)
689
620
551
483
414
345
276
207
100
90
80
70
60
50
40
30
(036) 60HZ CHARGING CHART
20.0 30.0 40.0 50.0 60.0 70.0 80.0
OUTDOOR TEMP
° F ° C
115 46
125 52
45 7
55 13
65 18
75 24
95 35
105 41
85 29
50JS500090
19
