BoilerFaultCodesYour boiler is failing to light its pilot light 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 required to ignite the main burner. The most common reason is a worn-out thermocouple that can no longer sense heat, or a pilot injector that has become blocked with dust and soot over time.
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.
Gas Safe Register →Protect yourself from future repair bills
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