Haier MRV 5-RC VP1-112B Service Manual page 222

Failure code
Outdoor Indoor unit LED status
digital display
tube:
123-1, 2
Indoor wired
Outdoor unit LED status
controller: 78,
7B
1. Model
MRV 5-RC series
2. Abnormity detection method
◆ Check the module is normal,
there is short circuit between P,
N, U, V, W
◆ Check whether the module
is fixed reliably and radiating is
good;
◆ Check the compressor
resistance is normal,
◆ Check if the wiring of
compressor UVW is correct,
frequency converter board and
module board connection is
reliable.
3. Abnormity confirmation
conditions
Hardware instantaneous over
current of the module rectifier
side
4. Possible causes
◆ Poor radiating caused the
module burned;
◆ The module is punctured to
cause a breakdown;
◆ Compressor winding
resistance too large
◆ UVW wiring short circuit, or
compressor line short circuit to
ground
◆ The compressor has a liquid
shock, causing starting current
or operating current too high
Normal
Failure diagnosis and troubleshooting
Diagnosis
Check if the supply voltage is normal
Check if the electrical box connect
correctly, compressor wires connect
reliably
Check if the inverter module is normal
If the resistance, insulation of the
compressor is normal
If there are other failures 112,114
Solve the failure
LED5 Failure description:
Hardware instantaneous over current of the
compressor module rectifier side
20 times
LED1 LED2
Normal
N
Y
N
Y
N
Y
N
Y
Y
219
Troubleshooting
Adjust the power supply.
Reconnect or re-fix it in
accordance with circuit
diagram.
Replace the inverter module
Replace the compressor