Carrier 48LC 04 Controls, Start-Up, Operation And Troubleshooting page 31

S Economizer Not Economizing When It Should
In this case, the economizer should be enabled, but for some
reason it's not providing free cooling.
S Damper Not Modulating
This issue represents a stuck, disconnected, or otherwise
inoperable damper that does not modulate open and close.
Alert Code T415 - - IAQ Input Out of Range
This alert occurs when the IAQ input (on ECB) is less than 3.5 mA
and the sensor is configured as installed. IAQ operation will be
disabled. Check sensor and wiring. This alert clears automatically.
ALARM
OR
DESCRIPTION
ALERT
NUMBER
Compressor A1 Safety Trip
Service Test --- Compressor A1 Safety Trip
T051
Compressor A1 Detected After Turnoff
Service Test --- Compressor A1 Detected After
Turnoff
Circuit A Saturated Condensing Temp Thermistor
T064
Failure
Circuit A Saturated Suction Temperature
T066
Thermistor Failure
T073 Outdoor Air Temperature Thermistor Failure
T074 Space Temperature Thermistor Failure
T075 Supply Air Temperature Thermistor Failure
T076 Return Air Thermistor Failure
T077 Space Relative Humidity Sensor Failure
T092 Circuit A Suction Pressure Transducer Failure
T102 Compressor Current Sensor Failure
Circuit A Loss of Charge
T110
Service Test --- Circuit A Loss of Charge
Circuit A High Discharge Pressure
T126
Service Test --- Circuit A High Discharge Pressure
Circuit A Low Refrigerant Pressure
T133
Service Test --- Circuit A Low Refrigerant
Pressure
Circuit A Failure To Pressurize
T143
Service Test --- Circuit A Failure to Pressurize
T153 Real Timeclock Hardware Failure
A154 Serial EEPROM Hardware Failure
T155 Serial EEPROM Storage Failure Error
A156 Critical Serial EEPROM Storage Fail Error
A157 A/D Hardware Failure
Circuit A Down Due to Failure
A163
Service Test --- Circuit A Down Due to Failure
Loss of communication with the Energy
T173
Management Module
T175 Loss of communication with VFD
Loss of communication with the Economizer
T179
Control Board
Loss of communication with the Economizer
T180
Actuator
A200 Linkage Timeout Error --- Comm Failure
A404 Fire Shutdown
T408 Dirty Air Filter
Fan Status Switch ON, fan commanded off
T409
Fan Status Switch OFF, fan commanded on
R---W1 Jumper Not Installed in Space Temp
Mode
T410
R---W1 Jumper Must Be Installed to Run Heat In
Service Test
Alert Code T416 - - OAQ Input Out of Range
This alert occurs when the OAQ input (on ECB) is less than 3.5
mA and the sensor is configured as installed. OAQ operation will
be disabled. Check sensor and wiring. This alert clears
automatically.
Alert Code A420 - - Supply VFD Fault
This alarm occurs when the VFD has faulted and communicates it to
the Main Base Board (MBB). The last VFD fault number can be
viewed as VFD1 Last Full code (Run Status
to VFD major component section for details on its alarms and faults.
The alarm will shut down the unit if the fan ramps down to 0%. This
alarm will automatically reset or can be reset through the display.
Table 6 – ComfortLink Alarm Codes
ACTION TAKEN BY RESET
CONTROL METHOD
Add Strike for Circuit A Automatic
Turn off all compressors Automatic
Limited Diagnostic Automatic
No Circuit A Cooling Automatic
No cooling with economizer Automatic
If U.CTL = 3, then no
Automatic
heating or cooling
No cooling with economizer
and No adaptive Automatic
compressor staging
If RAT .S = Yes, then no
Automatic
differential Dry Bulb control
If RH.S = Yes, then no
Automatic
indoor humidity control
Lockout Circuit A Manual
No Circuit A Cooling Automatic
Lockout Circuit A Manual
Shutdown Circuit A Automatic
Add Strike for Circuit A Automatic
Add Strike for Circuit A Automatic
No time and date schedule
Automatic
operation
Unit Shutdown Automatic
Unit operation errors Automatic
Unit Shutdown Automatic
Unit Shutdown Automatic
Lockout Circuit A Manual
No action Automatic
Unit Shutdown Automatic
No economizer operation Automatic
No economizer operation Automatic
No Linkage Operation fall
Automatic
back to local SPT
Unit Shutdown Automatic
Alert Generated Automatic
If IDF.F = YES,
then Manual,
If IDF.F = Yes, then Unit
otherwise
Shutdown
automatic
If IDF.F = YES,
then Manual,
If IDF.F = Yes, then Unit
otherwise
Shutdown
automatic
Unable to run heat Automatic
Unable to Test Heat Outputs Automatic
31
S.VFD
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PROBABLE CAUSE
High---pressure switch open. Compressor internal protection
open. Wiring error
Welded contactor
Faulty, shorted, or open thermistor caused by wiring error or
loose connection.
Circuit A Suction transducer internally forced inactive
Faulty, shorted, or open thermistor caused by wiring error or
loose connection.
Faulty, shorted, or open thermistor caused by wiring error or
loose connection.
Faulty, shorted, or open thermistor caused by wiring error or
loose connection.
Faulty, shorted, or open thermistor caused by wiring error or
loose connection.
Faulty, shorted, or open sensor caused by wiring error or
loose connection.
Faulty transducer, faulty 5---V power supply, or loose
connection
Miswired, bad Current board, or no board installed but
configured for it.
Low refrigerant or faulty suction pressure transducer
An overcharged system, high outdoor ambient temperature
coupled with dirty outdoor coil, plugged filter drier, or a faulty
high---pressure switch.
Low refrigerant charge, dirty filters, evaporator fan turning
backwards, loose or broken fan belt, plugged filter drier,
faulty transducer, excessively cold return air, or stuck open
economizer when the ambient temperature is low.
Wiring causing reverse rotation or faulty compressor
No time/date configured, software failure, or MBB failure
Software failure or MBB failure
Software failure or MBB failure
Software failure or MBB failure
Software failure or MBB failure
Circuit has 3 strikes or has been locked out by another alarm
MBB Software failure, reload software or replace board
Communication connection bad or miswired, misconfigured
VFD.
Communication wiring problem with ECB or faulty MBB or
ECB
Communication wiring problem with actuator.
Received a table write from Linkage before, now not
receiving any linkage commands
Smoke detected by smoke detector
Dirty Filter
Bad Fan Status Switch. Configuration incorrect.
Tripped Circuit Breaker. Broken belt. Bad indoor fan motor.
Configuration incorrect. Bad fan status switch.
Missing jumper wire
Missing jumper wire
LFC). Refer
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