Low-Voltage Detection - Daikin FTXS09HVJU Service Manual

Troubleshooting

4.23 Low-voltage Detection

U2
Remote
Controller
Display
An abnormal voltage drop is detected by checking the DC voltage detection circuit.
Method of
Malfunction
Detection
 The voltage being detected by the DC voltage detection circuit is judged to be below 150 V for
Malfunction
Decision
 The system is shut down if the error occurs 16 times.
Conditions
 Clearing condition: Continuous run for about 60 minutes (normal)
 Supply voltage not as specified
Supposed
 DC voltage detection circuit defective
Causes
 PAM control part(s) defective
 Short circuit inside the fan motor winding.
Troubleshooting
Service Diagnosis
0.1 second.
Be sure to turn off power switch before connect or disconnect connector,
Caution
or parts damage may be occurred.
Check the supply voltage.
Supply voltage
as specified?
YES
Rotate fan by hand.
Does fan rotate
smoothly?
YES
Turn on the
power again. System
restarted?
NO
Repeat a
NO
NO
(Precaution before turning on the power again)
Make sure the power has been off for
YES
Disturbance factors
* Noise * Power supply distortion
SiUS04-904
Correct the power supply.
Replace fan motor and
outdoor unit PCB.
Check for such factors for
an extended period of time.
* Try to get restarted a
couple of times.
Replace the outdoor unit
PCB.
(R0285)
143