BoilerFaultCodesYour boiler is failing to light the pilot flame or detect a steady flame, meaning it cannot start the heating process.
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 attempts to start up but cannot establish or maintain the small pilot flame needed to ignite the main burner. The most common reasons are a blocked pilot hole preventing gas flow or a worn-out sensor that can no longer tell the boiler it is safe to stay on. In some cases, the gas valve may be failing to release the fuel required to start the ignition process.
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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