Home/Boiler Fault Codes/Glow-worm F22
GLOW-WORM FAULT CODE
Glow-worm F22
Low water pressure — the system has insufficient pressure, or the boiler's pressure sensor has detected a drop, and has shut down to prevent damage.
WHAT F22 TYPICALLY INDICATES
Low water pressure — the system has insufficient pressure, or the boiler's pressure sensor has detected a drop, and has shut down to prevent damage.
WHAT TO DO
Check the gauge and top up via the filling loop if it's low, following the manual. If pressure drops again shortly after, 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 F22 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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