High Temperature Protection Of Indoor Coil In Heating Mode (J0) - Bosch Climate 5000 Series Service Manual

Service Manual

8.14 High temperature protection of indoor coil in heating mode (J0)

Error Code
Malfunction decision conditions
Supposed causes
Table 37
Troubleshooting:
Evaporator high temperature protection
Evaporator high temperature protection
Is the compressor operating?
s the compressor operating?
Yes
Is the outdoor ambient
temperature higher than
86°F (30°C)?
No
Is the air-outlet blocked?
Is the air-outlet blocked?
No
Is the indoor fan running
Is the indoor fan running
normally?
normally?
Yes
Are the heat exchanger and
Are the heat exchanger and
filter dirty
filter dirty
No
Replace the indoor main
Replace the indoor main
PCB
PCB
Figure 57
Bosch Thermotechnology Corp. | 04.2020
Bosch Climate 5000 Series Ductless Air Conditioner / Heat Pump Outdoor Unit | 59
J0
When evaporator coil temperature is more than 140°F (60°C), the unit stops. It starts again only when
the evaporator coil temperature is less than 129°F (54°C).
Faulty evaporator coil temperature sensor
Dirty heat exchanger
Faulty fan
Indoor PCB Faulty
No
Yes
Stop the system
Clean the air-outlet
Yes
Clean the air-outlet
Refer to the solution for the
Refer to the solution for the
malfunction of the fan speed being out
malfunction of the fan speed being out
No
of control . Find the cause and resolve
of control . Find the cause and resolve
the problem
the problem
Clean the heat exchanger and filter
Yes Clean the heat exchanger and filter
Check the
connec on between
T2 and the main PCB.
No
Have T2 and T2B been
Have T2 and T2B been
reversed?
reversed?
Yes
Is the resistance of T2
Is the resistance of T2
normal according to
No
normal according to
Appendix 1?
Appendix 1?
Yes
Correct the wiring
connec on.
Replace the
temperature sensor
Data subject to change