Service Manual
8.3 Zero crossing detection error (E2)
Error Code
Malfunction decision conditions
Supposed causes
Table 24
Troubleshooting:
Check if the connections and
power supply are normal. The
power supply should not exceed
10% of the rated voltage.
Indoor main PCB is
defective. Replace indoor
Figure 38
Bosch Thermotechnology Corp. | 04.2020
E2
When PCB does not receive zero crossing signal feedback for 4 minutes or the zero crossing signal time
interval is abnormal.
Connection mistake
Indoor PCB faulty
Yes
main PCB.
Bosch Climate 5000 Series Ductless Air Conditioner / Heat Pump Outdoor Unit | 45
Correct the connections. Turn on the
No
unit when the power supply is good.
Data subject to change