What does the Glow-worm Flexicom F99 fault code mean?
The F99 fault code on the Glow-worm Flexicom indicates an issue with the boiler’s technical support system, which may involve communication errors or internal faults. This error typically requires professional diagnosis to determine the underlying cause.
Common Causes
- Communication Failure: This can occur due to a malfunction in the control board or wiring issues that disrupt signals between components.
- Software Glitch: A software error in the boiler’s control system may lead to incorrect fault reporting, necessitating a reset or reprogramming.
Can I fix it myself? (DIY)
It is strongly advised to call a Gas Safe Engineer for this fault, as it involves technical support issues that could affect the safe operation of the boiler. Attempting DIY repairs may pose safety risks.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F99 fault could range from £150 to £300, depending on whether a control board replacement or software reprogramming is needed. This cost reflects the complexity of diagnosing and fixing electronic faults in modern boilers.