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

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188
Failure code
Outdoor
digital
display tube:
35-0, 1
Indoor wired
controller:
23
Indoor unit LED status
LED5 Failure description:
Four-way valve reversing failure
20 times
Outdoor unit LED status
LED1 LED2
Normal Normal
1. Model Diagnosis and troubleshooting
MRV 5-RC series
Diagnosis Troubleshooting
2. Abnormity detection method
◆
Check if the difference
between high and low pressure
of system exceeds 0.6MPa after
start and before failure alarm;
◆
Check if the unit lack of
refrigerant.
◆
Check the four-way valve of
unit for normal switching and
free from backflow.
◆
Check if the detection value of
high/low pressure sensor is correct.
◆
Check if the unit is beyond
the operation range.
3. Abnormity confirmation
conditions
In case of meeting one of the
following conditions after the
four-way valve is energized
for 3min and lasts for 10s,
it is judged as switching
completion:
•Tsuc-Tdef≥10 °C
•Pd-Ps≥βMpa
(Tao>-10°C , β=0.60;Tao≤-10 °C ,
β=0.40), otherwise, it is judged
as failure.
4. Possible causes
◆
The detection value of high/
low pressure sensor is incorrect;
◆
The refrigerant in the system
is insufficient;
◆
The four-way valve cannot be
switched normally or with backflow.
◆
The filter of compressor
suction pipe is blocked by
foreign matters;
◆
The detection value of Tsuc or
Tdef1/2 sensor is incorrect;
The power module cannot drive the
compressor operating normally;
◆
The operation environment
is beyond the allowed range.
Check if the difference between
high and low pressure of
system exceeds 0.6MPa after
start and before failure alarm
Check if the refrigerant in the system
is with leakage or insufficient.
Check if the detection value of low
pressure sensor is correct.
Check if the four-way valve of
outdoor unit is with backflow
and if the suction pipe filter of
compressor is blocked.
Check if it operates normally
after replacing with a normal
driver module.
Check if the allowed
operation range is exceeded.
Use the unit in accordance with
its allowed operation range.
Replace it correctly after
sales on site and ensure the
refrigerant is enough.
Troubleshoot if the detection
value of Tsuc or Tdef1/2 sensor
is correct and if the connection is
correct.
Rectify it correctly by after-sales
personnel on site.
Troubleshoot and rectify
it correctly by after-sales
personnel on site.
Replace the driver module
correctly.
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