SiMT041311E
Troubleshooting
Service Diagnosis
178
2.39 Improper Power Supply Wiring
Error Code
UA
Method of Error
Detection
Check for the incompatible power supply of DC part by using the DC voltage detection circuit.
Error Decision
Condition
The voltage detected by the DC voltage detection circuit is 350 V and more or 180 V and
less for more than 1 second.
If the error repeats, the system is shut down.
Reset condition: Continuous run for about 20 minutes without any other error
Supposed
Causes
Power supply voltage is not as specified.
Malfunction of DC voltage detection circuit
Troubleshooting
Correct the power supply.
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
NO
YES
Check the power supply voltage.
Turn off the power.
Replace the outdoor
unit PCB.
(R20444)
YES
Disturbance factors
∗
Noise
∗
Power supply distortion
Check for such factors for
a long term.
Turn on the power.
System restarted?
NO
Correct the connection.
YES
Electrical
components harness
connected properly?
NO
Is the
voltage fluctuation
within ±10% from the
rated value?