Mitsubishi Electric M Series Manual page 166

WALL-MOUNTED Inverter Heat Pump
MUZ-FD50VA
MUZ-FD50VAH
Power lamp
Abnormal point
(Indoor unit) (Failure mode/protection)
Communication error
11-time flash
between P.C. boards
Current sensor
Zero cross detecting circuit
Converter
Bus-bar voltage
(1)
Bus-bar voltage
(2)
Even if this protection stop is
performed continuously 3 times,
it does not mean the abnormality
in outdoor power system.
NOTE : Blinking patterns of this mode differ from the ones of "Troubleshooting check table".
C-164
LED indication
Condition
(Outdoor P.C. board)
LED 1 LED 2
Communication error occurs between
Lighting 6 times
the electronic control P.C. board and
power board for more than 10
seconds.
The communication between boards
protection stop is continuously
performed twice.
Lighting 7 times
A short or open circuit is detected in
the current sensor during compressor
operating.
Current sensor protection stop is
continuously performed twice.
5 times Goes
Zero cross signal cannot be detected
out
while the compressor is operating.
The protection stop of the zero
cross detecting circuit is
continuously performed 10 times.
5 times Goes
A failure is detected in the operation
out of the converter during operation.
5 times
Goes The bus-bar voltage exceeds 400V or
out falls to 200V or below during
compressor operating.
6 times
Goes
The bus-bar voltage exceeds 400V or
out
falls to 50V or below during
compressor operating.
M series
Indoor/outdoor
unit failure mode
recall function