Suction Pipe Temperature Thermistor Anomaly - Mitsubishi Heavy Industries FDTC50ZHXV Technical Manual

Error code
Remote controller: E53
1. Applicable model
Model FDC 71 – 250
2. Error detection method
When the suction pipe
temperature thermistor detects
anomalously low temperature
3. Condition of Error displayed
If the temperature thermistor
detects -50°C or lower for 5
seconds continuously within
10 minutes to 10 minutes 20
seconds after compressor ON,
the compressor stops. When
the compressor is restarted
automatically after 3-minutes
delay, if this anomaly ocuurs 3
times within 40 minute.
4. Presumable cause
• Defective suction pipe
temperature thermistor
connection
• Defective suction pipe
temperature thermistor
• Defective outdoor control
PCB
Note:
LED Green Red
Keeps flashing Stays Off
Indoor
Keeps flashing 1 time flash
Outdoor
5. Troubleshooting
Diagnosis
Is the connection
of suction pipe temperature thermistor
connector OK?
YES
Are the
characteristics of suction pipe
temperature thermistor OK?
Temperature-resistance characteristics
15
10
5
0
316
–
Suction pipe temperature
Content
thermistor anomaly
(Model FDC71 - 250)
NO
NO
YES
5kΩ at 25°C
10 20 30 40 50
Temperature (°C)
–
Countermeasure
Correct connection of
suction pipe temperature
thermistor connector.
Defective suction pipe
temperature thermistor 
Replace.
Replace outdoor control
PCB.
(Defective suction pipe
temperature thermistor
input circuit)