Troubleshooting - Haier MRV 5-RC VP1-112B Service Manual

5. Troubleshooting

Failure code
Outdoor Indoor unit LED status
digital
display tube:
20-0
Indoor wired Outdoor unit LED status
controller:
14
1. Model
MRV 5-RC series
2. Abnormity detection method
◆ Check if the sensor
connection is normal;
◆ Check if resistance
characteristic of the sensor is
normal;
◆ Check if the temperature
loop acquired by the PCB is
normal.
3. Abnormity confirmation
conditions
AD value is below 11 (open
circuit) or over 1012 (short
circuit) for 60 seconds,
sensor has no alarm when
abnormal in cooling mode.
4. Possible causes
◆ The connection of sensor is
not secure;
◆ The sensor is broken;
◆ The sensor is with
resistance drift;
◆ The temperature acquired
by PCB is not accurate.
Normal
Normal
Failure diagnosis and troubleshooting
Diagnosis
Check if the corresponding
connector of sensor is normal
Check if resistance
characteristic of the sensor
is normal
Check if the temperature
loop acquired by the
computer board is normal
LED5 Failure description:
Defrosting temperature sensors:
20 times Tdef failure
LED1 LED2
Normal
N
Y
N
Y
Y
174
Troubleshooting
Replace it correctly by after-
sales personnel on site.
Replace it correctly by after-
sales personnel on site.
Replace it correctly by after-
sales personnel on site.