220
Failure code
Outdoor
digital display
tube:
124-1, 2
Indoor wired
controller: 78,
7C
Indoor unit LED status
LED5 Failure description:
Compressor module three-phase power
failure
20 times
Outdoor unit LED status
LED1 LED2
Normal Normal
1. Model Failure diagnosis and troubleshooting
MRV 5-RC series
Diagnosis Troubleshooting
2. Abnormity detection method
◆
Check if the modules' R, S,
T are correct, if missing phase
◆
Check if the power supply of
the electrical box lack of phase,
if the voltage is too low
3. Abnormity conrmation
conditions
Module three-phase power
failure
4. Possible causes
◆
Module three-phase voltage
is too low
◆
Module three-phase power
lack of phase or imbalance
Check if the power supply voltage
too low or lack of phase
Check if the electrical box connect
correctly
Check if the inverter module connect
well
Check if the inverter module is
normal
Replace the electrical box to
compare
Reconnect or re-fix it in
accordance with wiring
diagram.
Replace the inverter module
Adjust the power supply.
Y
Y
Y
Y
N
N
N
N
Reconnect or re-fix it in
accordance with wiring
diagram.