Mitsubishi Electric M Series Manual page 284

CEILING CASSETTE Inverter Heat Pump
MLZ-KA25VA MLZ-KA35VA MLZ-KA50VA
Flow chart of the detailed outdoor unit failure mode recall function
Operational procedure
The outdoor unit might be abnormal.
Confirm if outdoor unit is abnormal according to the following procedures.
Confirm that the remote controller is in the failure mode recall
function.
With the remote controller headed towards the indoor unit, press TOO COOL or TOO
WARM button to adjust the set temperature to 25 .
Does OPERATION INDICATOR lamp on the indoor
unit blink at the interval of 0.5 seconds?
Blinks: The outdoor unit is abnormal.
Beeps are emitted at the same timing as the
blinking of OPERATION INDICATOR lamp. 2
The outdoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point.
Make sure to check at least two consecutive blinking cycles.
Releasing the failure mode recall function
Release the failure mode recall function by the following procedures.
Turn OFF the power supply and turn it ON again.
Press RESET button of the remote controller.
Deleting the memorized abnormal condition
After repairing the unit, recall the failure mode again according to
"Setting up the failure mode recall function" mentioned above.
Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature is displayed)
with the remote controller headed towards the indoor unit.
Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.
Release the failure mode recall function according to "Releasing the failure mode recall function"
mentioned above.
Note1. Make sure to release the failure mode recall function once it is set up, otherwise the unit cannot operate properly.
2. If the abnormal condition is not deleted from the memory, the last abnormal condition is kept memorized.
2.Blinking pattern when outdoor unit is abnormal:
2.5-second OFF
ON
OFF
C-282
1
Yes
(Blinks)
Repair the defective parts.
Blinking at 0.5-
3-second ON
second interval
No beep
Beeps
Repeated cycle
No
(OFF)
2
Release the failure mode recall function according
to the left mentioned procedure.
2.5-second OFF 3-second ON
No beep
Repeated cycle
M series
1. Regardless of normal or abnormal, 2 short
beeps are emitted as the signal is received.
The outdoor unit is normal.
Blinking at 0.5-
second interval
Beeps
Repeated cycle