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

Error code
E39
Remote controller:
Note (1) ( ) is for model 40~60.
1. Applicable model
All models
2. Error detection method
Detection of anomalously low
temperature (resistance) on
the discharge pipe temperature
thermistor
3. Condition of Error displayed
When the temperature thermistor
detects -10°C or lower for 5
seconds continuously within
10 minutes to 10 minutes 20
seconds after the compressor
ON, the compressor stops. After
3-minutes delay, the compressor
starts again automatically, but
if this anomalous temperature
is detected 3 times within 40
minutes.
4. Presumable cause
• Defective outdoor control
PCB
• Broken thermistor harness or
temperature sensing section
(Check molding.)
• Disconnected wire connection
(connector)
Note:
LED Green Red
Keeps flashing Stays Off
Indoor
Keeps flashing 1(8) time flash
Outdoor
5. Troubleshooting
Diagnosis
Is the
discharge pipe
temperature thermistor
connector connected
properly?
YES
Are the
characteristics
of discharge pipe
temperature
thermistor
OK?
• Model 40~71
Temperature-resistance characteristics
100
50
0
[T 90 ]
°C
0 20
• Model 100 - 250
Temperature-resistance characteristics
200
100
180
温
〔T?80?〕
度
160
T?80?
セ
140
ン
120
サ
抵
100
50
抗
80
60
(k)
40
20
0
0
0 20 40
0 50
温 度〔Ｔ〕 （?）
304
–
Content
Discharge pipe
temperature thermistor anomaly
NO
For the characteristics of discharge pipe
temperature thermistor, see the following graph.
NO
YES
40 60 80 100 120
Temperature (°C)
10
温
〔T?80?〕
度
セ
T?80?
ン
サ
抵
5
抗
(k)
0
60 80 100 120 140
80 100
Temperature (°C)
–
Countermeasure
Correct connector.
Defective discharge pipe
temperature thermistor 
Replace.
Defective outdoor control
PCB  Replace.
(Defective temperature
thermistor input circuit)
140
160