Ac Voltage Protection (J8) - Bosch Climate 5000 Series Service Manual

6 6 | Bosch Climate 5000 Series Ductless Air Conditioner / Heat Pump Outdoor Unit

8.21 AC Voltage protection (J8)

Error Code
Malfunction decision conditions
Supposed causes
Table 44
Troubleshooting:
AC power input voltage
AC power input voltage
Check whether the power
Check whether the power
voltage is normal.
voltage is normal.
Measure outdoor
terminal voltage
to check if it is normal.
Check if the voltage between
L and N is normal.
Check if input voltage of
bridge rectifier is normal.
Measure whether the voltage
Measure whether the voltage
between P and N is normal
between P and N is normal
Replace the IPM board, If the IPM and
Replace the IPM board,
main board are on the same board,
replace the outdoor main PCB
Figure 64
Data subject to change
J8
An abnormal voltage rise or drop is detected by checking the speci ed voltage detection circuit.
protection enabled
Yes
No
Yes
No
Yes
No
Yes
No
Yes
Yes
Abnormal power supply
Wiring mistake
Bridge rectifier faulty
IPM board faulty
Restart the unit when the power
Restart the unit when the power
No
supply normalizes
Check the connection
of power wires
Ensure wire connection
of L and N is firm
Ensure wire connection
bridge rectifier
Check whether
Check whether C
bridge rectifier is
bridge rectifier is
normal
normal
Yes
Replace the PFC module (If exists)
Replace the PF
No
Check wiring connection
of reactor or inductance
Yes
Check whether reactor
C heck whether reactor
or inductance is normal
o or inductance is normal
Replace the bridge
Replace the bridge
No
rectifier
rectifier
Replace reactor or
Replace reactor or
No
inductance
inductance
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