What does the Glow-worm Ultimate F103 fault code mean?
The F103 fault code indicates a warning related to the Domestic Hot Water (DHW) Printed Circuit Board (PCB) in the Glow-worm Ultimate boiler. This typically signifies a malfunction or communication issue within the PCB that controls the hot water function.
Common Causes
- PCB Failure: The PCB may have developed a fault due to age, overheating, or electrical issues, preventing it from properly managing the hot water system.
- Wiring Issues: Damaged or loose wiring connections to the PCB can disrupt communication and lead to the F103 error code being displayed.
Can I fix it myself? (DIY)
It is strongly advised to call a Gas Safe Engineer for any repairs related to the PCB, as working with gas and electrical components can be dangerous. Attempting DIY repairs without proper training may lead to further issues or safety hazards.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F103 fault code is approximately £250 to £350. This includes the cost of a replacement PCB and labour, as PCB replacements can be expensive and require professional installation.