To Next PageTo Next PageWhat does Fault Code C4 mean on my Viessmann B2TB004 Boiler?
If your Viessmann Boiler displays Fault Code C4, there is a communication error with the Open Therm extension. Check the Open Therm extension.
What does Fault Code d6 mean on my Viessmann B2TB004 Boiler?
If your Viessmann Boiler displays Fault Code d6, input DE1 reports a fault at extension EA1. Remove fault at appliance concerned.
What does Fault Code d8 mean on my Viessmann Boiler?
If your Viessmann Boiler displays Fault Code d8, input DE3 reports a fault at extension EA1. Remove fault at appliance concerned.
What does Fault Code E4 mean on my Viessmann Boiler?
If your Viessmann Boiler displays Fault Code E4, there is a fault with the supply voltage of 24V. Replace the control unit.
What to do if my Viessmann B2TB004 shows error F4?
If your Viessmann Boiler displays the error code F4, it indicates no flame signal. To resolve this, check the ionisation electrode and connecting cable, measure the ionisation current, check the gas pressure, check the gas train, ignition, ignition module, ignition electrodes and the condensate drain. After these checks, press the reset button R.
What does error code F2 mean on my Viessmann Boiler and how to fix it?
Error F2 on your Viessmann boiler indicates that the temperature limiter has responded. Address this by checking the heating system fill level, the circulation pump, and vent the system. Also, inspect the temperature limiter and connecting cables. Finally, press the reset button R.
How to fix error code F1 on a Viessmann Boiler?
Error code F1 indicates that the flue gas temperature limiter has responded. To fix this, check the heating system fill level, vent the system, and after the flue system has cooled down, press reset button R.
What should I do if my Viessmann Boiler displays error code Fd?
If your Viessmann Boiler shows error code Fd, it indicates a burner control unit fault. Check the ignition electrodes and connecting cables. Verify that there isn't a strong electromagnetic interference (EMC) field near the equipment. Press reset button R. If the fault persists, replace the control unit.
Why is my Viessmann Boiler showing error code F3?
If your Viessmann Boiler is showing error code F3, it means a flame signal is already present at burner start. To resolve this, check the ionisation electrode and connecting cable, then press reset button R.
How to troubleshoot error code E8 on a Viessmann B2TB004 Boiler?
If your Viessmann boiler displays error code E8, it indicates that the ionisation current lies outside the permissible range. To troubleshoot this, check the ionisation electrode and cable, then press the reset button R.
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