BoilerFaultCodesYour boiler has successfully lit the small pilot flame, but the main burner is failing to ignite to provide heat 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: PILOT LIT BUT NO MAINS GAS
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the initial pilot light is burning correctly, but the instruction to open the main gas supply is failing. The most common reason is a mechanical failure within the gas control valve or a faulty solenoid coil that is unable to physically pull open the valve to let gas reach the main burners.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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