Daikin Sky Air B-Series R-410A, Service Manual

Page: 194 / 338

Si21-205 Troubleshooting for Outdoor Unit (25/35 class)
Troubleshooting 183
6.13 Over-voltage Detection
Remote
Controller
Display
U2
Method of
Malfunction
Detection An abnormal voltage rise is detected by checking the specified over-voltage detection circuit.
Malfunction
Decision
Conditions An over-voltage signal is fed from the over-voltage detection circuit to the microcomputer
(The voltage is over 400V).
The system will be shut down if the error occurs 5 times.
Clearing condition: Continuous run for about 60 minutes (normal)
Supposed
Causes Supply voltage not as specified
Over-voltage detection circuit defective
PAM control part(s) defective
Troubleshooting
Note: If the model doesn’t have SPM, replace the outdoor unit PCB.
Check the supply voltage.
Correct the power supply.
Check for such factors for a
long term.
Replace the SPM.
(Replace the outdoor unit
PCB.)
(R2957)
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Supply voltage as
specified?
NO
YES
Turn on the
power again.
Error displayed again?
YES
Repeat a
couple of times.
NO
Disturbance factors
∗
Noise
∗
Power supply distortion