What does the Vaillant ecoTEC exclusive F97 fault code mean?
The F97 fault code indicates that the boiler is not meeting environmental standards, which may be due to emissions exceeding permissible limits. This can affect the boiler’s efficiency and compliance with regulations.
Common Causes
- Faulty Lambda Sensor: This sensor measures the combustion gases and can fail, leading to incorrect readings and emissions issues.
- Blocked Flue: A blockage in the flue system can prevent proper venting of gases, causing the boiler to operate outside of environmental standards.
Can I fix it myself? (DIY)
It is strongly advised to call a Gas Safe Engineer to address this issue, as it involves gas and electrical components that can be dangerous if handled improperly.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F97 fault could be around £250 to £400, primarily depending on whether the lambda sensor needs replacing or if the flue system requires cleaning or repair.