BoilerFaultCodesYour boiler is failing to ignite or detect a flame because there is an issue with the gas supply or the gas valve inside the unit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Gas circuit
What causes this fault?
This fault occurs when the boiler attempts to light but fails to establish or maintain a steady flame. The most common reason is that gas is not reaching the burner correctly, often due to a faulty internal gas valve or a problem with the ignition spark. It can also be caused by a sensor failing to detect the flame even if the burner has successfully lit.
This fault can be more common during the first cold snap of winter when the gas valve may stick after being used less frequently over the summer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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