What does the Viessmann Vitodens 200-W F98 fault code mean?
The F98 fault code on the Viessmann Vitodens 200-W indicates a problem related to the user loyalty feature, which may affect the boiler’s operational efficiency and user settings. This fault typically arises from issues with the control unit or software malfunctions.
Common Causes
- Control Unit Malfunction: A failure in the control unit can lead to incorrect readings or settings, triggering the F98 fault code.
- Software Issues: Outdated or corrupted software may cause the user loyalty feature to malfunction, resulting in this error code.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer to diagnose and resolve this issue, as it may involve complex electronic components that require professional expertise.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F98 fault code is around £150 to £250, primarily due to potential software updates or control unit replacements that may be necessary.