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122
T093
Circ B Suction Press Transducer Failure
Circuit shut down
Automatic
T094
Circ A EXV 1 Thermistor Failure
Circuit shut down
Automatic
T095
Circ A EXV 2 Thermistor Failure
Circuit shut down
Automatic
T096
Circ B EXV 1 Thermistor Failure
Circuit shut down
Automatic
T097
Circ B EXV 2 Thermistor Failure
Circuit shut down
Automatic
T098
Circuit A Liquid Temperature Thermistor Failure
Alert Only - no circuit prognostics
Automatic
T099
Circuit B Liquid Temperature Thermistor Failure
Alert Only - no circuit prognostics
Automatic
T100
Circ A Liquid Press Transducer Failure
Alert Only - no circuit prognostics
Automatic
T101
Circ B Liquid Press Transducer Failure
Alert Only - no circuit prognostics
Automatic
T110
Circuit A Loss of Charge
Circuit locked off
Manual
T111
Circuit B Loss of Charge
Circuit locked off
Manual
T112
Low Circuit A Charge Detected
Alert Only
Automatic
T113
Low Circuit B Charge Detected
Alert Only
Automatic
T114
High Circuit A Charge Detected
Alert Only
Automatic
T115
High Circuit B Charge Detected
Alert Only
Automatic
P120
Circuit A Low Saturated Suction Temp, Comp Shutdown
Circuit staged down
Automatic
T120
Circuit A Low Saturated Suction Temperature Alert
Circuit shut down
Automatic
A120
Circuit A Low Saturated Suction Temperature Alarm
Circuit locked off
Manual
P121
Circuit B Low Saturated Suction Temp, Comp Shutdown
Circuit staged down
Automatic
T121
Circuit B Low Saturated Suction Temperature Alert
Circuit shut down
Automatic
A121
Circuit B Low Saturated Suction Temperature Alarm
Circuit locked off
Manual
T122
Circuit A High Saturated Suction Temperature
Alert Only
Manual
T123
Circuit B High Saturated Suction Temperature
Alert Only
Manual
P126
Circuit A High Head Pressure, Comp Shutdown
Circuit stage down
Automatic
T126
Circuit A High Head Pressure Alert
Circuit shut down
Automatic
A126
Circuit A High Head Pressure Alarm
Circuit locked off
Manual
P127
Circuit B High Head Pressure, Comp Shutdown
Circuit stage down
Automatic
T127
Circuit B High Head Pressure Alert
Circuit shut down
Automatic
A127
Circuit B High Head Pressure Alarm
Circuit locked off
Manual
T128
Digital Scroll A1 High Discharge Temperature Alert
Digital compressor A1 shutdown
Automatic
A128
Digital Scroll A1 High Discharge Temperature Alarm
Digital compressor A1 locked off
Manual
A140
Reverse Rotation Detected
Stop unit
Manual
A150
Unit is in Emergency Stop
Unit shut down
Manual
A152
Unit Down due to Failure
No mechanical cooling available
Automatic
T153
Real Time Clock Hardware Failure
Unit shut down
Automatic
A154
Serial EEPROM Hardware Failure
Unit shut down
Automatic
T155
Serial EEPROM Storage Failure Error
Alert only
Automatic
A156
Critical Serial EEPROM Storage Fail Error
Unit shut down
Automatic
A157
A/D Hardware Failure
Unit shut down
Automatic
A169
EXV Board Communication Failure
Humidimizer control disabled
Automatic
T170
Loss of Communication with the Compressor Expansion Module
Compressors A3, A4, B3 and B4 disabled
Automatic
A171
Staged Gas Control Board Comm Failure
Staged gas control disabled
Automatic
T172
Control Expansion Module Comm Failure
All CEM board functions disabled
Automatic
A173
RXB board Communication Failure
Unit shut down
Automatic
A174
EXB board Communication Failure
All EXB board functions disabled
Automatic
A175
VFD1 Communication Failure
Unit shut down
Automatic
T176
VFD2 Communication Failure
No building pressure control
Automatic
T177
4-20 mA Demand Limit Failure
No demand limiting
Automatic
T178
4-20 mA Static Pressure Reset Fail
No static pressure reset
Automatic
A179
Cir. A EXV Board Communication Failure
Circuit shut down
Automatic
A180
Cir. B EXV Board Communication Failure
Circuit shut down
Automatic
T181
Loss of Communication with Outside Air Limit
Alert only
Automatic
A200
Linkage Timeout Error - Comm Failure
Resorts to local unit set points
Automatic
T210
Building Pressure Transducer Failure
No building pressure control function
Automatic
T211
Static Pressure Transducer Failure
No static pressure control
Automatic
T220
Indoor Air Quality Sensor Failure
No IAQ control
Automatic
T221
Outdoor Air Quality Sensor Failure
OAQ defaults to 400 ppm
Automatic
T229
Economizer Min Pos Override Input Failure
Operate without override
Automatic
T245
Outside Air CFM Sensor Failure
No OA CFM control
Automatic
T246
Supply Air CFM Sensor Failure
Unit shut down
Automatic
T247
Return Air CFM Sensor Failure
Unit shut down
Automatic
T248
Exhaust Air CFM Sensor Failure
Alert only
Automatic
T300
Space Temperature Below Limit
Alert only
Automatic
T301
Space Temperature Above Limit
Alert only
Automatic
T302
Supply Temperature Below Limit
Alert only
Automatic
T303
Supply Temperature Above Limit
Alert only
Automatic
T304
Return Temperature Below Limit
Alert only
Automatic
T305
Return Temperature Above Limit
Alert only
Automatic
Table 92 —
Alert and Alarm Codes (cont)
ALARM OR
ALERT
NUMBER
DESCRIPTION
ACTION TAKEN BY CONTROL
RESET METHOD
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 ...