Haier MRV 5-RC VP1-112B Service Manual page 192

Failure code
Outdoor Indoor unit LED status
digital
display tube:
36-0, 1
Indoor wired
Outdoor unit LED status
controller:
24
1. Model
MRV 5-RC series
2. Abnormity detection method
◆ Check if the temperature
detected by the oil temperature
sensor is correct.
◆ Check if the outdoor unit
SV31, SV32, LEVb, etc.
are with abnormal leakage
and check if the detected
temperature is correct;
◆ Check if the shutdown
indoor unit LEV of unit is closed
tightly, and if the running indoor
unit fan operates normally.
3. Abnormity confirmation
conditions
Toil1/Toil2-CT≤10°C lasts for
5min.
4. Possible causes
◆ The probe of oil temperature
sensor falls off or is with
unsecure connection;
◆ The probe of oil temperature
sensor is misplaced;
◆ The oil temperature sensor
is with resistance drift;
◆ The outdoor unit LEVb,
SV31 and SV32 are with
leakage;
◆ The terminal of outdoor
unit LEVa1, 2 and LEVb is
connected incorrectly;
◆ For the unit, there is LEV
leakage in shutdown indoor
unit and non-operation of fan in
operating indoor unit;
◆ The system refrigerant is too
much
◆ The operation environment
is beyond the allowed range.
Normal
Diagnosis and troubleshooting
Diagnosis
Check if the resistance of oil
temperature sensor is correct.
Y
Check if the sensor probe is secure
and if the position is correct.
Check if the indoor unit LEV of "OFF"
is closed tightly and if the indoor unit
fan of "ON" is normal.
Check if the terminal of
outdoor unit LEVb, SV31
and SV32 is connected
properly or is closed tightly.
Y
Check if the outdoor unit LEVa1, 2
and LEVb are connected properly
and correctly when heating.
Check if the unit is filled with
excessive refrigerant.
Fill with regular refrigerant in
accordance with standard quantity.
LED5 Failure description:
Outdoor compressor oil temperature (Toil1,
20 times Toil2) too low failure
LED1 LED2
Normal
N
N
Y
N
Y
N
N
Y
N
Y
189
Troubleshooting
Replace the oil temperature
sensor by after-sales personnel
on site.
Replace it correctly by after-sales
personnel on site.
[Note]: Check if it is inserted,
connected and intersected with
another compressor, especially
when a single compressor operates.
Replace the poor valve (with
leakage) and fan correctly by
after-sales personnel on site.
Replace the poor valve (with
leakage) and fan correctly by
after-sales personnel on site.
Replace it correctly by after-sales
personnel on site.
Check if the computer board
can normally control the related
electronic expansion valve and
solenoid valve, if not, replace it.