Bosch Climate 5000 Series Service Manual page 57

8.6.4 Outdoor temperature sensor (coil sensor T3,ambient sensor T4,
Compressor discharge sensor T5 indoor coil outlet pipe sensor T2B)
malfunction) (EC 52/EC 53/EC 54/EC 56/EC 50)
Error Code
Malfunction decision conditions
Supposed causes
Table 34
Troubleshooting:
Figure 57
Figure 58
Bosch Climate 5000 Series Ductless Air Conditioner / Heat Pump Multi Zone Outdoor Units (01.2023)
EC 52/EC 53/EC 54/EC 56/EC 50
If the sampling voltage is lower than 0.06V or higher than 4.94V, the LED will display the failure.
Improper / Incorrect Wiring
f
Sensor faulty
f
Indoor / Outdoor PCB faulty
f
Check the connections
between temperature
sensor and PCB.
the connections correct?
Yes
Check the resistance value
of the sensors via Appendix 1
and Appendix 2
Is it normal? Yes
No
Replace the sensor
No Correct the connections.
Replace indoor or outdoor PCB.
Outdoor room temperature sensor T4 is in open circuit or has short
f
circuited(EC 53)
Compressor discharge temperature sensor T5 is in open circuit or has
f
short circuited(EC 54)
Evaporator coil outlet temperature sensor T2B is in open circuit or has
f
short circuited(EC 56)
Service Manual
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