Cooling troubleshooting – Carrier 48/50PD05 User Manual
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Table 8 — ComfortLink™ Alarm Codes (cont)
ALARM
OR
ALERT
NUMBER
DESCRIPTION
ACTION TAKEN BY
CONTROL
RESET
METHOD
PROBABLE CAUSE
T178
Loss of Communication with the Capacity
Control Board
Unit shutdown ---HVAC
disable
Automatic
Communication wiring problem with AUX1 or faulty
MBB, ECB, or AUX1
T179
Loss of communication with the Economizer
Control Board
No economizer
operation
Automatic
Communication wiring problem with ECB or faulty
MBB, ECB, or AUX1
T180
Loss of communication with the Economizer
Actuator
No economizer
operation
Automatic
Communication wiring problem with actuator.
A200
Linkage Timeout Error --- Comm Failure
No Linkage Operation
fall back to local SPT
Automatic
Received a table write from Linkage before, now not
receiving any linked commands
A404
Fire Shutdown
Unit Shutdown
Automatic
Smoke detected by smoke detector
T408
Dirty Filter
Alert Generated
Automatic
Dirty Filter
T409
Fan Status Switch ON, Fan Contactor OFF
If IDF.F = Yes, then Unit
Shutdown
If IDF.F =
YES, then
Manual,
otherwise
automatic
Bad Fan Status Switch. Configuration incorrect.
Fan Status Switch OFF, Fan Contactor ON
If IDF.F = Yes, then Unit
Shutdown
If IDF.F =
YES, then
Manual,
otherwise
automatic
Tripped Circuit Breaker. Broken belt. Bad indoor fan
motor. Configuration incorrect. Bad fan status switch.
T414
Economizer Damper Actuator Out of
Calibration
Alert Generated
Automatic
Calibrate economizer (E.CAL). If problem still exist
then determine what is limiting economizer rotation.
Economizer Damper Actuator Torque Above
Load Limit
Alert Generated
Automatic
Actuator load too high. Check damper load.
Economizer Damper Actuator Hunting
Excessively
Alert Generated
Automatic
Damper position changing too quickly.
Economizer Damper Stuck or Jammed
Alert Generated
Automatic
No economizer motion. Check damper blades, gears,
and actuator.
Economizer Damper Actuator Mechanical
Failure
Alert Generated
Automatic
Check actuator and replace if necessary.
Economizer Damper Actuator Direction
Switch Wrong
Alert Generated
Automatic
Actuator direction control switch (CCW, CW) wrong.
T415
IAQ Input Out of Range
No IAQ Operations
Automatic
Bad sensor, bad wiring, or sensor configured
incorrectly.
T416
OAQ Input Out of Range
No OAQ Operations
Automatic
Bad sensor, bad wiring, or sensor configured
incorrectly.
LEGEND
ECB --
Economizer Control Board
IGC -- Integrated Gas Controller
MBB -- Main Base Board
OAT -- Outdoor--Air Thermistor
Cooling Troubleshooting
Use the Scrolling Marquee display or a CCN device to view the
cooling status display and the cooling diagnostic display (see
Appendix A) for information on the cooling operation. Check the
current alarms and alarm history for any cooling alarm codes and
correct any causes. (See Table 9.)
Verify any unique control configurations per installed site
requirements or accessories. If alarms conditions are corrected and
cleared, operation of the compressors and fans may be verified by
using the Service Test mode. (See Table 5.) See Table 9 for general
cooling service analysis.
48/
50P
D