Daikin B-Series Service Manual page 158

Si04-306E
5.1.8 Power Supply Waveforms Check
Check No.10 Measure the power supply waveform between pins 1 and 2 on the terminal board, and check
the waveform disturbance.
[Fig.1]
5.1.9 Inverter Units Refrigerant System Check
Check No.11
Service Diagnosis
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)
Refrigerant system check
Is
the discharge
thermister disconnected
from the holder?
NO
Check for gas leaks.
See the section on insufficient gas
detection.
[Fig.2]
YES
Check
Correct the problem.
Replace the refrigerant.
(R8349)
147