Troubleshooting - Carrier 40MBD Owner's Manual

TROUBLESHOOTING

Refer to Table 2 before contacting your local dealer.
INDOOR UNIT
Clean Air Filter*
Change Remote Control Batteries
OUTDOOR UNIT
Clean Outdoor Coil from Outside
Clean Outdoor Coil from Inside†
Blow Air Over Electric Parts†
Check Electric Connection Tightening†
Clean Fan Wheel†
Check Fan Tightening†
Clean Drain Pans†
* Increase frequency in dusty zones.
†
Maintenance to be carried out by qualified service personnel. Refer to the Installation Manual
PROBLEM
Unit/System Does Not Work
Cooling is Not Working Properly
Heating is Not Working Properly
Unit Stops During Operation
* Diagnostic lights are a combination of lights that will illuminate in the display area on the unit. They are a combination of the lights you see during normal operation.
OM-40MBD-04
Table 1 — Periodic Maintenance
Table 2 — Troubleshooting
POSSIBLE CAUSE
 The circuit breaker has tripped or a fuse has
blown.
Power failure
Diagnostic lights illuminate.*
 Voltage is too low.
 The filter is blocked by dust.
 Temperature is not set properly.
 A window or door is open.
 The outdoor unit is obstructed.
 The fan speed is too low.
 The operation mode is in FAN instead of
COOL.
The filter is blocked with dust.
 Temperature is set too low.
 A window or door is open.
 The outdoor unit is obstructed.
 The OFF timer is not operating correctly.
 Diagnostic lights illuminate.*
Specifications subject to change without notice.
EVERY MONTH EVERY 6 MONTHS

EVERY MONTH EVERY 6 MONTHS

SOLUTION
 Reset the circuit breaker or replace the fuse with the
specified replacement fuse.
Call your service representative.
 Call your service representative.
 Clean the air filter.
 Check the temperature and reset if necessary.
 Close the window or door.
 Remove the obstruction.
 Change the fan speed selection.
 Change the operating mode to COOL or reset the unit.
 Clean the air filter.
 Check the temperature and reset if necessary.
 Close the window or door.
 Remove the obstruction.
 Restart the operating mode.
 Call your service representative.
EVERY YEAR

EVERY YEAR






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