Mitsubishi Electric FDT125VNVF Technical Manual page 439

Indoor display
Error code
E39
Remote controller:
inverter PCB
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:
RUN light
Keeps flashing
Green LED
Outdoor
control PCB
Keeps flashing
Yellow LED
Outdoor
Keeps flashing
5. Troubleshooting
discharge pipe
temperature thermistor
connector connected
properly?
Are the
characteristics
of discharge pipe
temperature
thermistor
(Broken wire)
200
100
180
温
〔T 80 〕
度 160
セ
140
ン
120
サ
抵 100
50
抗
80
60
(k)
40
20
0
0
0
0
(Short circuit)
TIMER light
Content
4 times flash
Red LED
1 time flash
temperature thermistor anomaly
Diagnosis
Is the
YES
For the characteristics of discharge pipe
temperature thermistor, see the following graph.
OK?
YES
Temperature-resistance characteristics
T 80
T 80
20 40 60 80 100 120
50 80 100
Temperature (°C)
温 度〔 Ｔ〕 （ ）
438 438
- - - -
Discharge pipe
Countermeasure
Correct connector.
NO
Defective discharge pipe
NO
temperature thermistor ➞
Replace.
Defective outdoor control
PCB ➞ Replace.
(Defective temperature
thermistor input circuit)
10
温
〔T 80 〕
度
セ
ン
サ
抵
5
抗
(k)
0
140 160
'12 • PAC-T-174