Mitsubishi Electric MXZ-2F33VF4-E1 Service Manual page 185

12-3. INSTRUCTION OF TROUBLESHOOTING
• Check the indoor unit 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 12-6.
"Check of power supply".
• Indoor unit • COOL or HEAT
serial signal operation only
error Refer to 12-6.
Refer to 12-6. "Check of
"How to R.V. coil".
check
miswiring and
serial signal
error".
OBH790L
Both LED1 and
LED2 light.
• When cooling, heat
exchanger of
non-operating indoor
unit frosts.
• When heating, non-
operating indoor unit
gets warm.
Refer to 12-6.
"Check of LEV".
• When cooling, • When heating,
dew drops in the room does not get
non-operating warm.
indoor unit. Refer to 12-6.
Check of "How to check
mispiping. inverter/compressor".
Check mispiping,
shortage of capacity.
185
LED1 or LED2
has blinked.
Refer to 12-4.
"Troubleshooting check table".
• When cooling,
room does not
cool.
Refer to 12-6.
"How to check
inverter/
compressor".