Daikin FTXN25L Service Manual page 66

Description Heat sink overheat
Possible Root 1. Fin temperature rise due to short circuit.
cause 2. Fin temperature rise due to defective outdoor unit fan.
3. Fin thermistor defective.
4. Connector in poor contact.
5. Outdoor unit PCB defective.
6. Silicon grease is not applied properly on the radiation fin after replacing outdoor unit PCB.
Troubleshooting
ARXN/RXN50/60L
ARXN/RXN25/35M
ARXN/RXN50/60M,RXB50/60B
*Remark:
Refer to Appendix A for outdoor fan system check.(Page 77, item 6.7)
Refer to Appendix A for installation condition check. (Page 77, item 6.6)
Turn off the power and turn it on
again to start the system.
Error displayed
again?
No
Check the
outdoor fan.
Functioning
Radiation fin dirty?
Yes
Models
L4
Y e s
Has the PCB been
replaced?
No
Check the radiation fin
temperature.
Above A°C?
Yes
Malfunction
No
A°C
85
93
85
Service Diagnosis
Check if silicon grease is
Y e s
applied properly on the
radiation fin. If not, apply
the silicon grease.
No
Replace the outdoor unit
PCB.
Replace the outdoor fan
motor.
Correct the connectors and
fan motor leads.
Replace the outdoor unit
PCB.
Check the installation
condition.
Clean up the radiation fin.
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