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OM-40MBD-04 Specifications subject to change without notice.
11
TROUBLESHOOTING
Refer to Table 2 before contacting your local dealer.
Table 1 — Periodic Maintenance
* Increase frequency in dusty zones.
†
Maintenance to be carried out by qualified service personnel. Refer to the Installation Manual
Table 2 — Troubleshooting
* 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.
INDOOR UNIT
EVERY MONTH
EVERY 6 MONTHS
EVERY YEAR
Clean Air Filter*
Change Remote Control Batteries
OUTDOOR UNIT
EVERY MONTH
EVERY 6 MONTHS
EVERY YEAR
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†
PROBLEM
POSSIBLE CAUSE
SOLUTION
Unit/System Does Not Work
The circuit breaker has tripped or a fuse has
blown.
Power failure
Diagnostic lights illuminate.
*
Voltage is too low.
Reset the circuit breaker or replace the fuse with the
specified replacement fuse.
Call your service representative.
Call your service representative.
Cooling is Not Working Properly
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
.
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.
Heating is Not Working Properly
The filter is blocked with dust.
Temperature is set too low.
A window or door is open.
The outdoor unit is obstructed.
Clean the air filter.
Check the temperature and reset if necessary.
Close the window or door.
Remove the obstruction.
Unit Stops During Operation
The
OFF
timer is not operating correctly.
Diagnostic lights illuminate.
*
Restart the operating mode.
Call your service representative.