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87
Table 105 — Alert and Alarm Codes
LEGEND
ALARM OR
ALERT
NUMBER
DESCRIPTION
ACTION TAKEN BY CONTROL
RESET
METHOD
PROBABLE CAUSE
A051
Circuit A, Compressor 1 Stuck On Failure
Turn off all compressors
Manual
Welded Contact
P051
Circuit A, Compressor 1 Failure
Add strike to Compressor
Automatic
(max 3)
High pressure switch, compressor
current, wiring error
T051
Circuit A, Compressor 1 Failure
Compressor locked off
Manual
Exceeded 3 strike limit
A052
Circuit A, Compressor 2 Stuck On Failure
Turn off all compressors
Manual
Welded Contact
P052
Circuit A, Compressor 2 Failure
Add strike to Compressor
Automatic
(max 3)
High pressure switch, compressor
current, wiring error
T052
Circuit A, Compressor 2 Failure
Compressor locked off
Manual
Exceeded 3 strike limit
A055
Circuit B, Compressor 1 Stuck On Failure
Turn off all compressors
Manual
Welded Contact
P055
Circuit B, Compressor 1 Failure
Add strike to Compressor
Automatic
(max 3)
High pressure switch, compressor
current, wiring error
T055
Circuit B, Compressor 1 Failure
Compressor locked off
Manual
Exceeded 3 strike limit
A056
Circuit B, Compressor 2 Stuck On Failure
Turn off all compressors
Manual
Welded Contact
P056
Circuit B, Compressor 2 Failure
Add strike to Compressor
Automatic
(max 3)
High pressure switch, compressor
current, wiring error
T056
Circuit B, Compressor 2 Failure
Compressor locked off
Manual
Exceeded 3 strike limit
T064
Circuit A Saturated Condensing Thermistor Failure
Use OAT for head pressure control
Automatic Faulty thermistor or wiring error
T065
Circuit B Saturated Condensing Thermistor Failure
Use OAT for head pressure control
Automatic Faulty thermistor or wiring error
T072
Evaporator Discharge Reset Sensor Failure
Unit Shutdown
Automatic Faulty remote input on CEM board
T073
Outside Air Temperature Thermistor Failure
Stop use of economizer
Automatic Faulty thermistor or wiring error
T074
Space Temperature Thermistor Failure
Unit Shutdown
Automatic Faulty thermistor or wiring error
T075
Return Air Thermistor Failure
Continue to run unit
Automatic Faulty thermistor or wiring error
T076
Outside Air Relative Humidity Sensor Failure
Use OAT changeover control
Automatic Faulty sensor or wiring error
T078
Return Air Relative Humidity Sensor Failure
Use differential drybulb changeover
Automatic Faulty sensor or wiring error
T082
Space Temperature Offset Sensor Failure
Use Space temperature without offset
Automatic Faulty sensor or wiring error
T090
Circuit A Discharge Pressure Transducer Failure
Stop circuit
Automatic
Faulty sensor, wiring error
T091
Circuit B Discharge Pressure Transducer Failure
Stop circuit
Automatic
Faulty sensor, wiring error
T092
Circuit A Suction Pressure Transducer Failure
Stop circuit
Automatic
Faulty sensor, wiring error
T093
Circuit B Suction Pressure Transducer Failure
Stop circuit
Automatic
Faulty sensor, wiring error
T110
Circuit A Loss of Charge
Stop circuit
Manual
Low refrigerant charge
T111
Circuit B Loss of Charge
Stop circuit
Manual
Low refrigerant charge
A120
Circuit A Low Saturated Suction Temperature Alarm.
Stop circuit
Manual
Low refrigerant charge, low airflow,
dirty coil, broken fan belt, TXV
problem
P120
Circuit A Low Saturated Suction Temp-Comp A2 Shutdown
Compressor A2 Shutdown
Automatic
Low refrigerant charge, low airflow,
dirty coil, broken fan belt, TXV
problem
T120
Circuit A Low Saturated Suction Temperature Alert.
Stop circuit
Automatic
Low refrigerant charge, low airflow,
dirty coil, broken fan belt, TXV
problem
A121
Circuit B Low Saturated Suction Temperature Alarm.
Stop circuit
Manual
Low refrigerant charge, low airflow,
dirty coil, broken fan belt, TXV
problem
P121
Circuit B Low Saturated Suction Temp-Comp B2 Shutdown
Compressor B2 Shutdown
Automatic
Low refrigerant charge, low airflow,
dirty coil, broken fan belt, TXV
problem
T121
Circuit B Low Saturated Suction Temperature Alert.
Stop circuit
Automatic
Low refrigerant charge, low airflow,
dirty coil, broken fan belt, TXV
problem
T122
Circuit A High Saturated Suction Temperature
Stop circuit
Manual
TXV problem
T123
Circuit B High Saturated Suction Temperature
Stop circuit
Manual
TXV problem
T126
Circuit A High Head Pressure
Stop circuit
Automatic
Dirty condenser, condenser fan
failure
T127
Circuit B High Head Pressure
Stop circuit
Automatic
Dirty condenser, condenser fan
failure
A140
Reverse Rotation Detected
Stop unit
Manual
Incorrect Compressor Wiring
A150
Unit is in Emergency Stop
Stop unit
Manual
External shutdown command
T153
Real Time Clock Hardware Failure
Stop unit
Manual
Control Board failure, check lights
A154
Serial EEPROM Hardware Failure
Stop unit
Manual
Control Board failure, check lights
T155
Serial EEPROM Storage Failure Error
Stop unit
Manual
Control Board failure, check lights
A156
Critical Serial EEPROM Storage Failure Error
Stop unit
Manual
Control Board failure, check lights
A157
A/D Hardware Failure
Stop unit
Manual
Control Board failure, check lights
A171
Staged Gas Control Board Comm Failure
Stop gas heat
Automatic
Control Board failure, check lights
A172
Controls Expansion Module Comm Failure
Stop options on CEM
Automatic
Control Board failure, check lights
A173
ECB1 Board Communication Failure
Stop economizer & power exh
Automatic
Control Board failure, check lights
A174
ECB2 Board Communication Failure
Stop unit
Automatic
Control Board failure, check lights
T177
4-20 MA Demand Limit Failure
Stop demand limiting
Automatic
Input failure, wiring error
T178
4-20 MA Static Pressure Reset/VFD Fail
Stop static pressure reset/VFD
Automatic
Input Failure, wiring error
A200
Linkage Timeout Error - Communication Failure
Stop unit
Manual
Wiring errors, board failures
T210
Building Pressure Transducer Failure
Close economizer, stop exhaust
Automatic
Sensor failure, wiring error
T211
Static Pressure Transducer Failure
Stop unit
Automatic
Sensor failure, wiring error
T220
Indoor Air Quality Sensor Failure
Stop IAQ control
Automatic
Sensor failure, wiring error
T221
Outdoor Air Quality Sensor Failure
Use a default value for IAQ
Automatic
Sensor failure, wiring error
T229
Economizer Minimum Position Override Input Failure
Use software configured
minimum
Automatic
Input failure, wiring error
A
—
Alarm
P
—
Pre-Alert
T
—
Alert
Summary of Contents for WEATHERMAKER 48AJ020
Page 95: ...95 Fig 13 Typical Main Control Box Wiring Schematic A48 7787 ...
Page 96: ...96 TO NEXT PAGE Fig 14 Auxiliary Control Box Wiring Schematic A48 7294 ...
Page 98: ...98 Fig 15 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown A48 6866 ...
Page 102: ...102 TO NEXT PAGE Fig 18 Typical Power Schematic Size 051 and 060 Units Shown A48 7298 ...
Page 104: ...104 Fig 19 Controls Option Wiring Schematic A48 7810 ...
Page 105: ...105 Fig 20 Small Chassis Component Location Size 020 035 Units A48 7301 ...
Page 106: ...106 Fig 21 Large Chassis Component Locations Size 036 060 Units A48 7302 ...