Bosch Condens 8300i W Installation And Maintenance Instructions Manual page 50

Troubleshooting
Fault text on the display, description
2955 B Boiler does not support the parameters set
for the hydraulic configuration
2956 O Hydraulic configuration at the boiler
activated
2957 V Boiler electr. system fault
2961 V No fan signal available
2962
2963 B The heat exchanger sensor or both supply
and heat exchanger sensors are defect
2965 B Flow temperature too high
2966 B Flow temperature rise in heat exchanger too
rapid
2971 B System pressure too low
2972 Mains voltage too low
2980 V The unit has been locked for safety reasons
after at least five locking faults have
occurred within 15 minutes.
2981 V The unit was switched off and on again with
the safety lock (fault code 2980) in place.
Table 30 Indicators and fault displays
50
Remedy
Check hydraulic settings, change if necessary.
• Low-loss header
• Internal DHW circuit (cylinder charging circuit)
• Heating circuit 1
• Heating pump in appliance
–
1. Reset control device / burner control unit.
2. Reconnect electrical connections at control device / burner control unit correctly.
3. Replace the control device/burner control unit.
1. Check fan and connecting lead.
2. Check mains voltage.
1. Connect the plug to the temperature sensor correctly.
2. Connect the plug to the control device correctly.
3. Attach the temperature sensor correctly.
4. Check the temperature sensor, replace if necessary.
5. Check temperature sensor connecting lead, replace if necessary.
1. Ensure that the heating circulation is working correctly.
2. Check pump setting, adjust to match heating system if necessary.
3. Connect the plug to the temperature sensor correctly.
4. Connect the plug to the control device correctly.
5. Attach the temperature sensor correctly.
6. Check the temperature sensor, replace if necessary.
7. Check temperature sensor connecting lead, replace if necessary.
1. Ensure that the heating circulation is working correctly.
2. Check pump setting, adjust to match heating system if necessary.
3. Connect the plug to the temperature sensor correctly.
4. Connect the plug to the control device correctly.
5. Attach the temperature sensor correctly.
6. Check the temperature sensor, replace if necessary.
7. Check temperature sensor connecting lead, replace if necessary.
1. Vent the heating system.
2. Check the heating system for tightness.
3. Top up water until the target pressure is reached.
4. Check the pressure sensor, replace if necessary.
5. Check the pressure sensor cable, replace if necessary.
1. Establish supply voltage of at least 196 VAC.
2. Replace burner control unit.
The safety lock may only be lifted by a specialised contractor after troubleshooting and a
subsequent on-site system inspection have been successful.
1. Diagnose and remedy the malfunction.
2. Check the complete system, including sensors and harnesses
3. Switch unit off and on again.
Fault code 2981 is displayed.
The safety lock may only be lifted by a specialised contractor after troubleshooting and a
subsequent on-site system inspection have been successful.
1. Reset the unit within 10 minutes after switching it on.
2. Reset the unit again after 22 to 28 seconds..
The lock is removed and the unit returns to normal operation.
3. Double-check the last 10 faults in the fault history to confirm the fault has been
remedied
Condens 8300i W – 6721841533 (2022/12)