Mitsubishi Heavy Industries FDT28KXE6A Service Manual page 88

Error code
E41(E51)
Remote controller:
E41(E51)-1, 2*1
7-segment display:
*1 E41-1 (E51-1) : CM1, E41-2 (E51-2) : CM2 *2 E41-1 (E51-1) : 1 time flash, E41-2 (E51-2) : 2 time flash
1. Applicable model
Outdoor unit
2. Error detection method
When anomalously high
temperature is detected by
power transistor temperature
thermistor (Tho-P1)
3. Condition of error displayed
Anomalously high temperature
of power transistor is detected 5
times within 60 minutes (E41).
Or it is detected for 15 minutes
continuously (E51)
4. Presumable cause
• Power transistor anomaly
• Power transistor temperature
thermistor anomaly
• Improperly fixing of power
transistor to radiator fin
• Inverter PCB anomaly
• Outdoor fan motor anomaly
• Anomalous cooling fan motor
for inverter
• Inadequate installation space
of outdoor unit
Note:
The operating conditions of cooling fan for inverter is shown in the right figure.
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 2
Outdoor
5. Troubleshooting
Diagnosis
Save data for 30 minutes before stopping in Mente PC
Does the outdoor fan run ?
YES
Reset power supply and restart
Does the
error recur when restarting?
YES
Is the
cooling fan for inverter running?
YES
Is 15V
of power for control PCB
detected?
YES
After power OFF
Is the
connection of power
transistor temperature thermistor
OK?
(Check short-circuit or breakage
of harness)
YES
Is the
characteristics of power transitor
temperature thermistor OK? *
YES
Is the fixing
of power transistor OK?
(Check tightening of screws or
application of radiation
silicon)
86
–
Content
Power transistor overheat
* Refer the characterristics
of power transistor temperature
thermistor to E56
–
Countermeasure
Check and save the data of
operating conditions
Check the temperature of
power transistor
Check the operation of
outdoor fan and cooling fan
Repair it according to the
NO
troubleshooting procedure
of E48
Check it as much as
possible under the operating
conditions for 30 minutes
before error occurred
Wait and see.
NO
Continue to obain data, if
possible (Keep connecting
the Mente PC)
If the cooling fan does not
NO
run in spite of the operation
ON range, check the
voltage at the connector of
cooling fan.
If the 220/240V is detected,
repalce cooling fan motor.
If 0V is detected, replace
outdoor control PCB
After checking the loose
NO
connection of connetor
or breakage of harness,
replace inverter PCB
Connect the connector of
NO
thermistor securely.
Or replace power transistor
temperature thermistor
NO Replace power transistor
temperature thermistor
Fix power transistor on to
NO
the radiation fin with proper
application of radiation
silicon
Replace power transistor
YES
ON
OFF
81°C 85°C
Power transistor thermistor temperature