Home/Boiler Fault Codes/Vaillant F22
VAILLANT FAULT CODE
Vaillant F22
Indicates insufficient water pressure within the boiler system.
WHAT F22 TYPICALLY INDICATES
Indicates insufficient water pressure within the boiler system.
WHAT TO DO
Check the pressure gauge and top up using the filling loop if it reads below the range marked on the gauge (typically around 1 bar). If pressure keeps dropping after topping up, 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 Vaillant 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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