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Troubleshooting . . . . . . . . . . . . . . 103
Thermistor Troubleshooting . . . . . . . . . . . . . . . . . 103
Transducer Troubleshooting . . . . . . . . . . . . . . . . . 103
Forcing Inputs and Outputs . . . . . . . . . . . . . . . . . . 103
Run Status Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Alarms and Alerts . . . . . . . . . . . . . . . . . . . . . . . . . . 121
MAJOR SYSTEM COMPONENTS . . . . . . . . . . . . . . 134
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Factory-Installed Components . . . . . . . . . . . . . . . . 150
Accessory Control Components . . . . . . . . . . . . . . 161
SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Service Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Electronic Expansion Valve (EXV) . . . . . . . . . . . . . 171
Refrigeration Circuits . . . . . . . . . . . . . . . . . . . . . . . 171
Gas System Adjustment (48N Only) . . . . . . . . . . . 184
Moisture/Liquid Indicator . . . . . . . . . . . . . . . . . . . . 184
Filter Drier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Liquid Line Service Valves . . . . . . . . . . . . . . . . . . . 185
Protective Devices . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Temperature Relief Devices . . . . . . . . . . . . . . . . . . 185
Control Circuit, 115 V . . . . . . . . . . . . . . . . . . . . . . . 185
Control Circuit, 24 V . . . . . . . . . . . . . . . . . . . . . . . . 186
Gas Heat (48N Only) . . . . . . . . . . . . . . . . . . . . . . . . 186
Compressor Removal . . . . . . . . . . . . . . . . . . . . . . . 186
Compressor Replacement . . . . . . . . . . . . . . . . . . . 186
APPENDIX A
—
LOCAL DISPLAY TABLES . . . . . . 187
APPENDIX B
—
CCN TABLES. . . . . . . . . . . . . . . . . 206
APPENDIX C
—
UNIT STAGING TABLES. . . . . . . . 228
APPENDIX D
—
VFD INFORMATION . . . . . . . . . . . 230
APPENDIX E
—
MODE SELECTION PROCESS . . . 241
APPENDIX F
—
BACNET COMMUNICATION
OPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
APPENDIX G
—
OPTIONAL MOTORMASTER V
CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
INDEX. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
UNIT PRE-START-UP AND START-UP
CHECKLISTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . CL-1
CONTROLS SET POINT AND
CONFIGURATION LOG . . . . . . . . . . . . . . . . . . . . CL-5
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment can be
hazardous due to system pressure and electrical components.
Only trained and qualified service personnel should install, re
-
pair, or service air-conditioning equipment. Untrained personnel
can perform the basic maintenance functions of replacing filters.
Trained service personnel should perform all other operations.
When working on air-conditioning equipment, observe precau
-
tions in the literature, tags and labels attached to the unit, and
other safety precautions that may apply. Follow all safety
codes. Wear safety glasses and work gloves. Use quenching
cloth for unbrazing operations. Have fire extinguishers avail
-
able for all brazing operations.
WARNING
ELECTRICAL SHOCK HAZARD
Before performing service or maintenance operation on
unit, turn off and lock off main power switch to unit. Elec
-
trical shock can cause personal injury and death. Shut off
all power to this equipment during installation and service.
The unit may have an internal non-fused disconnect or a
field-installed disconnect.
CAUTION
UNIT DAMAGE HAZARD
This unit uses a microprocessor-based electronic control
system.
Do not
use jumpers or other tools to short out com
-
ponents or to bypass or otherwise depart from recommend
-
ed procedures. Any short-to-ground of the control board or
accompanying wiring may destroy the electronic modules
or electrical components.
WARNING
1. Improper installation, adjustment, alteration, service, or
maintenance can cause property damage, personal injury,
or loss of life. Refer to the User’s Information Manual
provided with this unit for more details.
2. Do not store or use gasoline or other flammable vapors
and liquids in the vicinity of this or any other appliance.
DANGER
DO NOT USE TORCH to remove any component. System
contains oil and refrigerant under pressure.
To remove a component, wear protective gloves and gog
-
gles and proceed as follows:
a. Shut off electrical power to unit.
b. Recover refrigerant to relieve all pressure from system
using both high-pressure and low pressure ports.
c. Traces of vapor should be displaced with nitrogen and
the work area should be well ventilated. Refrigerant in
contact with an open flame produces toxic gases.
d. Cut component connection tubing with tubing cutter and
remove component from unit. Use a pan to catch any oil
that may come out of the lines and as a gage for how
much oil to add to the system.
e. Carefully un-sweat remaining tubing stubs when neces
-
sary. Oil can ignite when exposed to torch flame.
Failure to follow these procedures may result in personal
injury or death.
CAUTION
DO NOT re-use compressor oil or any oil that has been ex
-
posed to the atmosphere. Dispose of oil per local codes and
regulations. DO NOT leave refrigerant system open to air
any longer than the actual time required to service the
equipment. Seal circuits being serviced and charge with dry
nitrogen to prevent oil contamination when timely repairs
cannot be completed. Failure to follow these procedures
may result in damage to equipment.
Summary of Contents for WeatherExpert 48N2
Page 135: ...135 Fig 18 48 50N Typical Power Schematic Nominal 075 Ton Unit Shown ...
Page 136: ...136 Fig 19 48 50N Typical Power Schematic Nominal Ton 90 150 Units Shown ...
Page 137: ...137 Fig 20 48 50N Main Base Board Input Output Connections ...
Page 138: ...138 Fig 21 48 50N RXB EXB CEM Input Output Connections a48 9307 ...
Page 139: ...139 Fig 22 48 50N EXV SCB Input Output Connections a48 9308 ...
Page 140: ...140 Fig 23 48N Typical Modulating Gas Heat Unit Control Wiring ...
Page 141: ...141 Fig 24 50N Typical Electric Heat Unit Control Wiring ...
Page 144: ...144 Fig 27 48N Typical Gas Heat Section Wiring Nominal Ton 120 to 150 Units ...
Page 145: ...145 Fig 28 48 50N Typical Power Component Control Wiring 460 v ...
Page 146: ...146 Fig 29 48 50N Component Control Wiring 575 v Nominal Ton 075 to 150 Units ...
Page 147: ...147 Fig 30 48 50N Component Arrangement Power Box ...
Page 148: ...148 Fig 31 48 50N Component Arrangement Control Box ...
Page 240: ...240 APPENDIX D VFD INFORMATION CONT Fig G VFD Bypass Wiring Diagram WHEN USED ...