Daikin AT12BV1LS Pocket Manual page 163

Troubleshooting
5.4.9 Power Supply Waveforms Check
Check
No.10
5.4.10 Inverter Units Refrigerant System Check
Check
No.11
162
Measure the power supply waveform between pins 1
and 3 on the terminal board, and check the waveform
disturbance.
Check to see if the power supply waveform is a sine
wave (Fig.1).
Check to see if there is waveform disturbance near
the zero cross (sections circled in Fig.2)
[Fig.1]
Refrigerant system check
Is
the discharge
thermister disconnected
from the holder?
NO
Is any moisture
found in sight glass.
NO
Check for gas leaks.
See the section on insufficient
gas detection.
YES
[Fig.2]
YES
Correct the problem.
YES
Conduct vacuum
Conduct the
drying.
check after
operating the
equipment for
a sufficient
length of time.
Replace the
refrigerant.
Service Diagnosis
Si10-417
(R1445)