Daikin RXYQ96PYDN, Service Manual

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Troubleshooting by Indication on the Remote Controller SiUS34-801A_b
408 Troubleshooting
3.42
P4
Outdoor Unit: Malfunction of Inverter Radiating Fin
Temperature Rise Sensor
Remote
Controller
Display
P4
Applicable
Models
RXYQ72P~240PYDN, PTJU
REYQ72P~240PYDN, PTJU
Method of
Malfunction
Detection
Resistance of radiation fin thermistor is detected when the compressor is not operating.
Malfunction
Decision
Conditions When the resistance value of thermistor becomes a value equivalent to open or short circuited
status.
Malfunction is not decided while the unit operation is continued.
"P4" will be displayed by pressing the inspection button.
Supposed
Causes
Defect of radiator fin temperature sensor
Defect of inverter PC board
Faulty inverter compressor
Faulty fan motor
Troubleshooting
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Replace the inverter PC
board.
NO
YES
NO
NO
YES
NO
Measure resistance value of
the radiation fin thermistor.
Is the
thermistor resistance
value normal?
Replace the fan motor.
Replace the inverter PC
board.
Continue operation.
Replace the
compressor (M1C).
YES
The fan
motor's insulation
resistance is not more
than 1M
Ω
.
Does the
malfunction recur when
the power supply
turns ON?
YES
The INV
compressor's insulation
resistance is not more
than 100k
Ω
.
* Disconnect the connector (X111A) from the fin
thermistor, and then check the thermistor.
*