BoilerFaultCodesYour boiler has failed to light the pilot flame or cannot verify that the burner is safely lit, resulting in no heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition, pilot or flame proving fault.
What causes this fault?
This fault occurs when the boiler tries to start but fails to establish or maintain the small pilot flame needed to light the main burner. The most common reasons are a blocked pilot hole preventing gas flow or a worn-out sensor that can no longer detect the heat from the flame. Without confirmation that it is safe to stay lit, the boiler shuts down as a safety precaution.
This issue often appears in autumn when the boiler is first switched back on after a long summer break, as debris or dust can settle in the pilot assembly during periods of inactivity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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