Daikin CTX Series Service Manual page 72

DAMA-SM-21-003
Troubleshooting
Reference
Check No.01 Refer to P.85
Reference
Check No.12 Refer to P.86
Reference
Check No.14 Refer to P.88
Note
When replacing the defective thermistor(s), replace the thermistor as ASSY.
Service Diagnosis
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
Caution
Discharge
YES
pipe thermistor
disconnected?
NO
NG
Check the thermistors
• Discharge pipe thermistor
OK
Connectors are
NO
properly connected?
• Connector S40
• 2 terminals of OL (Q1L)
YES
Disconnect the connector S40
from the PCB.
Check
Resistance
the resistance ∞
between the 2 terminals on
connector S40.
Nearly 0 Ω
NG
Check the electronic
expansion valve.
OK
NG
Check the four way
valve
OK
NG
Check the refrigerant
line. • Refrigerant shortage
• Water mixed
• Stop valve
OK
Disconnect the 2 terminals
of the OL (Q1L).
Check the
Resistance
resistance
between the 2
terminals of the OL
(Q1L).
Nearly 0 Ω
applicable to CTX series (mode)
Troubleshooting
Insert the thermistor in
position.
Replace the discharge pipe
thermistor.
Connect the connectors
properly.
∞
Replace the OL (Q1L)
Replace the OL harness.
Replace the electronic expansion
valve or the coil
Replace the four way valve or the
coil.
Replace the outdoor unit PCB
(main PCB).
Refer to the refrigerant line
check procedure.
Replace the outdoor unit PCB
(main PCB).
67