Panasonic cu-4ks24nbu User Manual

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8.  TROUBLESHOOTING (BEFORE CALLING FOR SERVICE)
8-1.  Precautions before Performing Inspection or Repair
Both the indoor unit and outdoor unit include electronic control circuits. 
Be sure to pay attention to the following before inspecting or repairing the 
outdoor-side electronic circuits.
High-capacity electrolytic capacitors are used inside the outdoor unit controller (inverter). They retain an 
electrical charge (charging voltage DC 311 V) even after the power is turned OFF, and some time is required 
for the charge to dissipate.
Be careful not to touch any electrified parts before the control circuit board Power Lamp (red) turns OFF.
If the outdoor control circuit board is normal, approximately 180 seconds will be required for the charge to 
dissipate. However, allow at least 30 minutes for the charge to dissipate if it is thought there might be trouble 
with the outdoor control circuit board.
For example, if the outdoor control circuit board fuse has blown, approximately 30 minutes will be required to 
discharge the high-capacity electrolytic capacitors.
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