Low Pressure Anomaly - Mitsubishi Heavy Industries KX6 series Service Manual

Error code
E49
Remote controller:
E49
7-segment display:
1. Applicable model
Outdoor unit
2. Error detection method
Detection of anomalously low
pressure
3. Condition of error displayed
• At start up after power on:
When the low pressure sensor
detects lower than 0.003MPa
for 60 seconds continuously.
And if this anomaly occurs 2
times.
• During operation:
When the low pressure sensor
detects 0.134MPa or lower
for 30 seconds coninuously.
And if this anomaly occurs 5
times within 60 minutes
4. Presumable cause
• Low pressure sensor (PSL)
anomaly
• Service valves closed
• EEV anomaly (EEV closed)
• Insufficient refrigerant
amount
• Clogging at EEV or strainer
Note:
Check whether the indoor unit is connected to other outdoor superlink network.
If the error does not recur, connect the Mente PC and continue to collect data.
LED Green Red
Keeps flashing Stays Off
Indoor
Keeps flashing 1 time flash
Outdoor
5. Troubleshooting
Diagnosis
Save data for 30 minutes before stopping in Mente PC
Reset power supply and restart.
error occur immediately after
NO
Does the low
pressure fluctuate after the
startup?
YES
* The sensor
characteristics is shown in
Is the opening
degree of EEV
for evaporator side
flucturing?
YES
Is the checked
result of harness and insulation
of EEV coil OK?
YES
Does the
EEV operate
normally by judging
from Mente PC
data, etc?
YES
89
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Content

Low pressure anomaly

Does the
YES
the startup?
Is the
NO
connection of sensor connector
OK?
YES
Are the
sensor characteristics
OK?*
YES
Page 91
Is the
NO
connection of
thermistor connector for
heat exchanger
OK?
YES
Are the thermistor
characteristics OK?
YES
NO
Isn't EEV
NO
or strainer
clogged?
NO
–
'10 • KX-SM-148
Countermeasure
Check and save the data of
operating conditions
Check error status.
Is the refrigerant amount
OK
Check additional
refrigerant amount charged
at site according to the
piping length instructed
on the label pasted on the
panel of the unit.
Check whether the service
valves are open.
NO Correct the connection
of low pressure sensor
connector
Replace low pressure
NO
sensor.
Replace outdoor control
PCB.
Correct the connection of
NO
temperature thermistor
connector of heat
exchanger
Replace temperature
thermistor of heat
NO
exchanger at evaporator
side.
Replace control PCB at
evaporator side.
Replace EEV coil.
YES
Replace EEV main body or
strainer.
Check for short circuit of
airflow of heat exchanger
at evaporator side and for
fan motor anomaly