Daikin SkyAir RZQ200 · 250C7Y1B Service Manual page 194

SiBE26-701
Check No. 10 Check for factors causing wet operation
Referring to the Fault Tree Analysis (FTA) shown below, identify the faulty points.
Refrigerant
dwelling
Excessive refrigerant charging
Faulty superheat
degree control
Wet operation
Decreased
evaporation
capacity
∗: Reference values for superheat degree to be used in the judgment of wet operation
Suction pipe superheat degree: 4˚C or more
(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.)
Troubleshooting
Faulty crankcase heater
Frequent starts and stops of the compressor
Faulty valve coil
Faulty electronic
expansion valve
Faulty valve body
Faulty low pressure sensor
Faulty suction pipe thermistor
Faulty control
Faulty control PC board
Dirty evaporator
← Is the heat exchanger clogged?
Decre-
Decreased
ased
fan airflow
fan
rate
output
Diagnosis by Remote Controller
← Refer to
← 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?
← Can the fan motor be
Faulty fan motor
rotated with hands?
Are the motor coil
resistance and insulation
Faulty control PC board
normal?
(including capacity setting)
Discharge pipe superheat degree: 5˚C or less
Check No. 9 .
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