
17
LOW-CHARGE COOLING
Using Cooling Charging Charts (Fig. 21-24), vary refrigerant until
the conditions of the appropriate chart are met. Note the charging
charts are different from the type normally used. Charts are based
on charging the units to the correct superheat for the various oper-
ating conditions. Accurate pressure gage and temperature sensing
devices are required. Connect the pressure gage to the service port
on the suction line. Mount the temperature sensing device on the
suction line and insulate it so that outdoor ambient temperature
does not affect the reading. Indoor-air cfm must be within the nor-
mal operating range of the unit.
EXAMPLE:
Model 581J*28
Circuit A
Outdoor Temperature . . . . . . . . . . . . . . . . . . . . . . . . . 85°F (29°C)
Suction Pressure . . . . . . . . . . . . . . . . . . . . . . . . 125 psig (862 kPa)
Suction Temperature should be . . . . . . . . . . . . . . . . . 63°F (17°C)
Circuit B
Outdoor Temperature . . . . . . . . . . . . . . . . . . . . . . . . . .85°F (29°C)
Suction Pressure . . . . . . . . . . . . . . . . . . . . . . . . 120 psig (827 kPa)
Suction Temperature should be . . . . . . . . . . . . . . . . . .58°F (14°C)
USING THE COOLING CHARGING CHARTS
Take the outdoor ambient temperature and read the suction pres-
sure gage. Refer to chart to determine what suction temperature
should be. If suction temperature is high, add refrigerant.
If suction temperature is low, carefully recover some of the charge.
Recheck the suction pressure as charge is adjusted.
Select the appropriate unit charging chart from Fig. 21-24.
Take the outdoor ambient temperature and read the suction pres-
sure gage. Refer to chart to determine what suction temperature
should be. If suction temperature is high, add refrigerant. If suc-
tion temperature is low, carefully recover some of the charge. Re-
check the suction pressure as charge is adjusted.
For sizes 17-28, perform this procedure once for Circuit A and
once for Circuit B.
581J SIZE DESIGNATION
NOMINAL TON
REFERENCE
17
15
20
17.5
24
20
28
25
Содержание 581J 17-28 Series
Страница 18: ...18 COOLING CHARGING CHARTS Fig 21 Cooling Charging Chart 15 Ton ...
Страница 19: ...19 Fig 22 Cooling Charging Chart 17 5 Ton ...
Страница 20: ...20 Fig 23 Cooling Charging Chart 20 Ton ...
Страница 21: ...21 Fig 24 Cooling Charging Chart 25 Ton ...
Страница 36: ...36 Fig 47 Unit Control Box IGC Location IGC Board IGC Board Side view Front view ...
Страница 39: ...39 Fig 50 Integrated Gas Control IGC Board RED LED STATUS ...
Страница 45: ...45 Fig 56 RTU Open Overlay for Economizer Wiring ...
Страница 46: ...46 Fig 57 VFD Overlay for W2770 Controller Wiring ...
Страница 84: ...84 Fig B 581J 17 28 Control Diagram 208 230 3 60 460 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Страница 85: ...85 Fig C 581J 17 28 Power Diagram 208 230 3 60 APPENDIX D WIRING DIAGRAMS ...
Страница 86: ...86 Fig D 581J 17 28 Power Diagram 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Страница 87: ...87 Fig E 581J 17 28 Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Страница 88: ...88 Fig F 581J 17 28 Control Diagram with Perfect Humidity System APPENDIX D WIRING DIAGRAMS ...
Страница 89: ...89 Fig G 581J 17 28 Power Diagram 208 230 3 60 with Perfect Humidity System APPENDIX D WIRING DIAGRAMS ...
Страница 90: ...90 Fig H 581J 17 28 Power Diagram 460 3 60 with Perfect Humidity System APPENDIX D WIRING DIAGRAMS ...
Страница 91: ...91 Fig I 581J 17 28 Power Diagram 575 3 60 with Perfect Humidity System APPENDIX D WIRING DIAGRAMS ...
Страница 92: ...92 Fig J RTU OPEN Wiring Diagram APPENDIX D WIRING DIAGRAMS ...
Страница 93: ...93 Fig K RTU OPEN Wiring Diagram with Perfect Humidity System APPENDIX D WIRING DIAGRAMS ...