Daikin 4MXL-T Series Service Manual page 221

SiUS121827E
Troubleshooting
Reference
Check No.01 Refer to P.232
Reference
Check No.13 Refer to P.237
Reference
Check No.14 Refer to P.237
Part 6 Service Diagnosis
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Four way valve
coil disconnected (loose)?
NO
Harness
disconnected?
NO
Check the continuity of the four way
valve coil and harness.
Disconnect the harness from the
connector.
Resistance
between harnesses
about 1000 ~ 2000 Ω?
YES
Check No. 13
Check the four way valve
switching output.
OK
Any thermistor
disconnected?
NO
Check No. 01
Check the thermistors.
OK
Check No. 14
Check the refrigerant line.
OK
YES
YES
NO
NG
YES
NG
NG
∗ Refrigerant shortage
∗ Water mixed
∗ Stop valve
Troubleshooting for Outdoor Unit
Correct the four way valve
coil.
Reconnect the harness.
Replace the four way
valve coil.
Replace the outdoor
unit PCB (main PCB).
Reconnect the
thermistor(s).
Replace the defective
thermistor(s).
Refer to the refrigerant line
check procedure.
Replace the four way valve
(defective or dust-clogged).
(R20405)
215