What does the Viessmann Vitodens 100-W F80 fault code mean?
The F80 fault code on the Viessmann Vitodens 100-W indicates a problem with the surge protection system, which is designed to safeguard the boiler’s electronic components from voltage spikes. This fault can lead to operational issues and may prevent the boiler from functioning correctly.
Common Causes
- Electrical Surge: A sudden spike in electrical voltage can damage the surge protection components.
- Faulty Surge Protection Module: The surge protection module itself may be defective or worn out, requiring replacement.
Can I fix it myself? (DIY)
It is highly recommended to call a Gas Safe Engineer for this issue, as it involves electrical components that can be dangerous to handle without proper training and certification.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F80 fault code is around £150 to £250, primarily due to the need for professional diagnosis and potential replacement of the surge protection module.