What does the Worcester Bosch Greenstar Si F86 fault code mean?
The F86 fault code indicates a problem with the system diagnostics of the Worcester Bosch Greenstar Si boiler. This typically suggests that the boiler’s internal monitoring system has detected an issue that prevents it from operating correctly.
Common Causes
- Faulty PCB: A malfunctioning printed circuit board can disrupt the boiler’s ability to process diagnostic information.
- Wiring Issues: Damaged or loose wiring connections can lead to communication failures between components, triggering the F86 fault.
Can I fix it myself? (DIY)
It is highly recommended to call a Gas Safe Engineer for this fault, as it involves electrical components and diagnostics that require professional expertise to ensure safety and compliance with regulations.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F86 fault could be around £200 to £300, primarily due to the potential need for a new PCB or extensive wiring repairs, which can be labour-intensive and require specialist parts.