Daikin FTXN25L Service Manual page 57

Service Diagnosis
Description HEAT EXCHANGER OVERHEAT
Possible Root 1. The installation space is not large enough.
cause 2. Faulty outdoor fan motor.
3. Faulty EXV.
4. Faulty outdoor heat exchanger thermistor.
5. Faulty stop valve.
6. Dirty heat exchanger.
7. Unit overcharge.
8. Defective outdoor unit PCB.
Troubleshooting
*Remark:
Refer to Appendix A for thermistor resistance checking procedures.(Page 72, item 6.1)
Refer to Appendix A for Electronic Expansion Valve (EXV) checking procedures. (Page 74, item 6.2)
Refer to Appendix A for Inverter unit refrigerant check procedures. (Page 75, item 6.4)
Refer to Appendix A for Installation condition check. (Page 77, item 6.6)
49
Check the installation space.
Check the
installation
condition.
Functioning
Check the
outdoor fan.
Functioning
Check the
electronic expansion
valve.
Functioning
Check the
outdoor heat exchanger
thermistor.
Functioning
F6
Malfunction
Malfunction
Malfunction
Malfunction
Change the installation
location or direction.
Clean the outdoor heat
exchanger.
Replace the outdoor fan
motor.
Reconnect the connector or
fan motor lead wires.
Replace the electronic
expansion valve or the coil.
Replace the outdoor unit PCB.
Replace the outdoor heat
exchanger thermistor.
Replace the outdoor unit PCB.