BoilerFaultCodesYour boiler is failing to light the small internal flame needed to start the main burner, which means your heating and hot water will not work.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Is there a spark at pilot burner? Check lead continuity and inspect electrode and lead for damage.
What causes this fault?
This fault occurs when the boiler's ignition system fails to create the small pilot flame required to safely light the main burner. The most common reasons are a worn-out spark electrode that can no longer produce a spark, or a tiny blockage in the pilot injector preventing gas from reaching the ignition point.
This issue often surfaces during the first cold spell of autumn when a boiler that has been idle over summer is suddenly asked to work hard, causing aging ignition components to finally fail.
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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