Home/Boiler Fault Codes/Glow-worm F1
GLOW-WORM FAULT CODE
Glow-worm F1
An ignition fault — the boiler attempted to light but no flame was detected.
WHAT F1 TYPICALLY INDICATES
An ignition fault — the boiler attempted to light but no flame was detected.
WHAT TO DO
Confirm the gas supply is on. Beyond that, This is not a DIY fix — it requires a Gas Safe registered engineer to diagnose and repair safely.
A NOTE ON GAS SAFE REGISTRATION
Any work on the gas side of a boiler in the UK legally requires a Gas Safe registered engineer, it isn't optional. Our engineers are fully Gas Safe registered, and you're always welcome to ask to see ID on the day. This page is general information about what a fault code typically indicates; it is not a substitute for an engineer diagnosing your specific boiler.
Seeing Glow-worm F1 on your boiler?
Tell us the code and your postcode. A fully Gas Safe registered engineer will diagnose the actual cause before quoting a fix.
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