Check For Factors Causing Wet Operation - Daikin R71FUV1 Service Manual

Si20-701_B
CHECK 9

Check for Factors Causing Wet Operation

Referring to the Fault Tree Analysis (FTA) shown below,
identify the defective points.
Refrigerant
dwelling
Excessive refrigerant
charging
Defective
superheated
degree control
Wet
operation
Decreased
evaporation
capacity
Note:
Reference values for superheated degree to be used in
the judgement of wet operation
(1) Suction pipe superheated degree: 4°C or more
(2) Discharge pipe superheated degree: 5°C or less
(The values above must be used only for reference
purposes. Even it is operated within the range above,
operation may be normal in other conditions.)
474
Troubleshooting by Remote Controller
Defective crankcase
heater
Frequent starts and
stops of the compressor
Defective
valve coil
Defective electronic
expansion valve
Defective
valve body
Defective low
pressure
sensor
Defective
Defective control suction pipe
thermistor
Defective
control PCB
Dirty evaporator
Decreased
Decreased
fan airflow
fan output
rate
← Refer to
CHECK 10
← Are the coil resistance and
insulation normal?
← Are the voltage
characteristics normal?
← Is the connector properly
connected?
Are the thermistor resistance
characteristics normal?
← Is the pressure value
checked with the Service
Checker corresponding to
the measurement of the
sensor?
← Is the heat exchanger
clogged?
← Can the fan motor
Defective
fan motor
be rotated with
hands?
Defective Are the motor coil
control resistance and
PCB
insulation normal?
(including
capacity
setting)