Daikin FTKM-U Series Service Manual page 67

SiMX042215E
Supposed  Disconnection of the discharge pipe thermistor, indoor or outdoor heat exchanger thermistor,
Causes
 Closed stop valve
 Refrigerant shortage (refrigerant leakage)
 Poor compression performance of compressor
 Defective electronic expansion valve (electronic expansion valve type model only)
Troubleshooting
Reference
Check No.01 Refer to P.90
Part 6 Service Diagnosis
room or outdoor temperature thermistor
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Any thermistor
disconnected?
NO
Stop valve closed?
NO
Check for refrigerant shortage.
Oil leak at relay pipe
connections?
NO
Oil leak at internal
piping?
NO
Change for a specified amount of
fresh refrigerant.
Refrigerant shortage error
again?
NO
YES
∗ Discharge pipe thermistor
∗ Indoor or outdoor heat exchanger thermistor
∗ Room temperature thermistor
∗ Outdoor temperature thermistor
YES
YES
YES
Compressor vibrating
too much?
YES
YES
Check No. 01
Check the thermistors.
OK
Replace the outdoor unit PCB
(main PCB).
Error again?
NO
Troubleshooting
Reconnect the thermistor(s).
Open the stop valve.
Repair the pipe flare or
replace the union.
NO
Check if any harnesses are
in contact with the piping
and correct as required.
Also, replace any cracked
pipes.
Check the connection of the
power transistor harness.
Also, replace any cracked
pipes.
NG
Replace the defective
thermistor(s).
YES
Replace the compressor.
Completed.
Completed.
(R24716)
63