4 6 |
Bosch Climate 5000 Series Ductless Air Conditioner / Heat Pump Multi Zone Outdoor Units
Service Manual
08.2020
|
Bosch Thermotechnology Corp.
Data subject to change
8.6.5 High / Low voltage protection (E5)
Error Code
E5
Malfunction decision conditions
An abnormal voltage rise or drop is detected by built-in logic in PCB
Supposed causes
f
Power supply problems
f
System problems, such as leakage or blockage
f
Outdoor PCB faulty
Table 23
Troubleshooting:
Figure 51
Voltage protection
Check the voltage of
outdoor unit power; is
the voltage between
L(L1) and N(L2)
about 187~264VAC
Check the power supply
Check whether the voltage of IPM
board P and N(GND) is normal?
DC277— 356V for 18K & 27K models
DC277- 410V for for 36K & 48K models
Replace bridge rectifiers,
and then check whether the
system can run normally
(for
48K model)*
Replace IPM board, and
then check whether the
system can run normally
Replace outdoor PCB
Yes
No
No
No
No
Yes
Problem is solved
Yes
Yes
* The bridge rectifier can be only
replaced on 48K model. On all
other models, ODU PCBs should
be replaced as the bridge rectifier
is embedded in PCBs
