Mitsubishi Heavy Industries FDT28KXE6A Service Manual page 84

Error code
E37
Remote controller:
E37-1, 2, 3, 4, 5, 6*1
7-segment display:
*1 E37-1: one time flash (Tho-R1), E37-2: 2 time flash (Tho-R2), E37-3: 3 time flash (Tho-R3), E37-4: 4 time flash (Tho-R4), E37-5: 5 time flash (Tho-SC), E37-6: 6 time flash (Tho-H)
1. Applicable model
Outdoor unit
2. Error detection method
Detection of anomalously low
temperature (resistance)
of Tho-R or Tho-SC or Tho-H
3. Condition of error displayed
• If -50°C or lower is detected for 5
seconds continuously within 2-minutes to
2-minutes 20-seconds after the compressor
ON, the compressor stops. And after
3-minutes delay, the compressor starts
again automatically, but if this anomalous
temperature is detected 3 times within 40
minutes after the initial detection.
• If -50°C or lower is detected for 5 seconds
continuously within 20 seconds after power ON
4. Presumable cause
• Broken thermistor harness or
the internal wire of sensing
section (Check the molded
section as well)
• Disconnection of thermistor
harness connection (connector)
• Outdoor control PCB anomaly
Note:
LED Green Red
Keeps flashing Stays Off
Indoor
Keeps flashing *1
Outdoor
5. Troubleshooting
Diagnosis
Save data for 30 minutes before stopping in Mente PC
Is the
connector of
thermistor connected
properly?
YES
Are the
characteristics of
thermistor
OK?*2
*2
Check several times to prove any poor connection
Outdoor heat exchanger temperature thermistor (Tho-R1~R6)
Sub-cooling coil thermistor (Tho-SC, Tho-H)
Temperature-resistance characteristics
Temperature (°C)
82
–
Outdoor heat exchanger
Content
temperature termistor (Tho-R) and subcooling coil
temperature thermistor (Tho-SC,-H) anomaly
NO
NO
YES
5kΩ at 25°C
–
Countermeasure
Check and save the data of
operating conditions
Check the conditions whether
it occurs immediately after the
power on or during operation
or stopping.
Check the sensed value.
Compare the temperature
on Mente PC with actual
measured value
Insert the connector
securely
Replace Thermistor
(Tho-SC, Tho-H, Tho-R)
Replace outdoor control
PCB