Mitsubishi Electric MXZ-3E54VA-E1 Service Manual page 89

11-3. INSTRUCTION OF TROUBLESHOOTING
• Check the indoor unit with referring to the indoor unit service manual, and confirm that there is any problem in the indoor
unit.
Then, check the outdoor unit with referring to this page.
Operation start
Check the outdoor unit
LED indicator.
Both LED1 and
LED2 are OFF.
Refer to 11-6.
"Check of power supply".
• Indoor unit • COOL or
serial signal HEAT
error operation only
Refer to 11-6. Refer to 11-6.
"How to "Check of
check R.V. coil".
miswiring and
serial signal
error".
OBH723D
Both LED1 and
LED2 are lighting.
• When cooling, heat
exchanger of
non-operating indoor
unit frosts.
• When heating, non-
operating indoor unit
gets warm.
Refer to 11-6.
"Check of LEV".
• When cooling • When heating,
dew drops in the room does not get
non-operating warm.
indoor unit.
Refer to 11-6.
Check of "How to check
mispiping. inverter/compressor".
Check mispiping,
shortage of capacity.
89
LED1 or LED2
has blinked.
Refer to 11-4.
"Troubleshooting check table".
• When cooling,
room is not
cool.
Refer to 11-6.
"How to check
inverter/
compressor".