Power Supply Voltage Abnormality - Daikin RZQ Series FCQ20EVA Service Manual

SiME281501E

4.39 Power Supply Voltage Abnormality

U2
Error Code
Applicable RZQ
Models
Method of Error
The error is detected according to the voltage of main circuit capacitor built in the inverter and
Detection power supply voltage.
Error Decision
When the voltage of main circuit capacitor built in the inverter and power supply voltage drop or
Conditions when the power failure of several tens of ms or more is generated.
 Remote controller does not decide the abnormality.
 Drop in power supply voltage (180 V or less)
Supposed
 Instantaneous power failure
Causes
 Inverter open phase (Phase T)
 Defective outdoor unit inverter PCB
 Defective outdoor unit fan motor
Troubleshooting
Caution
Be sure to turn off the power switch before connecting or disconnecting connectors, or parts may be damaged.
on outdoor unit PCB. (Is the
voltage insufficient?)
supply voltage within the
Is the wiring correct?
When the compressor is running,
measure the voltage between + and -
of electrolytic capacitor (C+, C-).
measured voltage 220 VDC or
Service Diagnosis
Check LED
NO
YES
Is the power
NO
standard range?
YES
NO
YES
Is the
YES
more?
NO
Troubleshooting by Remote Controller
External factor
Field factors
Correct the wiring.
Monitor the voltage
(Instantaneous voltage drop)
Replace the outdoor unit
inverter PCB.
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