BoilerFaultCodesYour boiler is failing to start up because the small ignition flame is not lighting properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PILOT WILL NOT LIGHT
What causes this fault?
This fault occurs when the boiler's safety system cannot detect a steady pilot flame, preventing it from safely firing the main burner. The most common cause is a worn-out thermocouple that no longer senses heat, or a tiny blockage in the pilot injector that stops gas from reaching the ignition point.
This issue is frequently seen after a long summer break, as dust can settle in the pilot assembly or the gas valve can become stiff through lack of use.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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