BoilerFaultCodesYour boiler is failing to light the gas or cannot confirm that a flame is present, meaning the system has shut down for safety.
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 happens when the boiler attempts to start up but cannot successfully ignite the gas or detect a steady flame. It is often caused by a blocked pilot light burner or a worn-out ignition spark, which prevents the main burner from firing up safely. In some cases, the internal control board may also fail to recognise that the flame is lit, prompting the system to shut down for your protection.
This issue often surfaces during the first cold spell of autumn when the boiler is worked harder after being mostly idle throughout the summer.
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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