Haier MRV 5-RC VP1-112B Service Manual page 221

Failure code
Outdoor Indoor unit LED status
digital
display tube:
122-1, 2
Indoor wired Outdoor unit LED status
controller: 7A
1. Model
MRV 5-RC series
2. Abnormity detection method
◆ Check if the temperature
acquisition circuit of inverter
board is normal.
◆ Check if the resistance of
temperature sensor is normal.
◆ Check if they are connected
correctly
3. Abnormity confirmation
conditions
The temperature sensor is
disconnected or the resistance
is incorrect.
4. Possible causes
◆ The resistance of
temperature sensor is found
with drift.
◆ The inverter board acquires
inaccurate temperature.
Normal
Failure diagnosis and troubleshooting
Diagnosis
Check if the sensor and
variable frequency board is
connected correctly.
Check if the sensor
resistance is normal.
Replace the variable
frequency board.
LED5 Failure description:
Radiator temp. sensor of compressor mo-
20 times dule is abnormal.
LED1 LED2
Normal
N
Y
N
Y
218
Troubleshooting
Adjust the connection
between temperature sensor
and variable frequency
board.
Replace the sensor.