What does the Vaillant ecoTEC plus F86 fault code mean?
The F86 fault code on the Vaillant ecoTEC plus indicates a service issue with the heating system, typically related to the need for maintenance or a malfunction in the system’s components. This error often suggests that the boiler requires a thorough inspection or servicing to restore proper functionality.
Common Causes
- Insufficient Maintenance: Lack of regular servicing can lead to buildup of debris or wear in components, triggering the F86 fault.
- Faulty Sensors: Malfunctioning temperature or pressure sensors can incorrectly signal a service requirement, resulting in the F86 code.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this fault, as it may involve complex issues that require professional expertise. Attempting to fix it yourself could lead to safety hazards or further damage.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F86 fault could range from £150 to £300, depending on whether it requires sensor replacement or a full service. This cost reflects the need for professional labour and potential replacement parts.