5.Troubleshooting
Diagnosis
Countermeasure
Is the fan of gas
cooler rotating?
NO
YES
YES
Save the Mente PC data of 30 minutes
before stopping
Reset the power source and restart operation
After power OFF
After
restarting operation, does the
same error reappear?
NO
YES
Is DC15V
of power source voltage detected
at the C19 terminal of
inverter PCB?
NO
Is the
connection of power
transistor sensor connector OK?
(Check short circuit and
disconnection of
wiring harness)
Is the
power transistor
mounted properly?
(Check tightning of screws and
application of silicon
for radiation)
NO
NO
NO
YES
YES
Is the
characteristics of power
transitor temperature sensor
OK?*
* See characteristic of sensor
for details.
YES
YES
Is the
inverter cooling fan
rotating?
NO
• Check the operation status and
record it.
• Check the power transistor
temperature.
• Check the operation of the fan of
gas cooler and the operation of
inverter cooling fan.
Rectify it according to the
troubleshooting procedure of E48.
Restart operation under the
operating conditions 30 minutes
before error occurred as possible
as you can.
Wait and see.
(If possible, collect the operation
data continuously.)
If it does not run despite its
operation range, check the voltage
at connector.
If 400V is detected, replace fan
motor.
If 0V is detected, replace control
PCB.
After checking loose connection
of connector or disconnection of
wiring harness, replace inverter
PCB.
Connect the connector of sensor
securely.
Or replace the sensor.
Replace the power transistor
sensor.
Apply the silicon for radiation to
the power transistor and mount
the power transistor on to the
radiation fin securely.
Replace the power transistor.
When E41 is displayed on the
7-segment LED display
Error signal from power
transistor is detected 5 times
within 60 minutes. (E41)
Or error signal from power
transistor is detected for 15
minutes continuously (E51)
• Power transistor anomaly
• Power transistor temperature
sensor anomaly
• Anomalous power source to
inverter PCB
Note: Inverter cooling fan is operated under the condition mentioned at right.
If the same error does not reappear, continue to get data with Mente PC.
Error code
Remote control:
7-segment display:
LED
Green
Red
Keep
flashing
*2
Content
–
*1
E41(E51) -1
Power transistor overheat (CM1)
ON
OFF
55°C
Power transistor temperature sensor
67°C
*1 E41 (E51) -1: CM1
*2 E41 (E51) -1: 1-time flash
Condensing
unit
All models
1. Applicable model
2. Error detection method
3. Condition of error displayed
4. Presumable cause
User Guide | Optyma™ iCO2
54 | BC408445719305en-000101
© Danfoss | Climate Solutions | 2023.01 | LCA012A030