BoilerFaultCodesYour boiler is still detecting a flame even though the gas supply should have been cut off, which is a safety concern that prevents the unit from operating.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Ionisation detected after the gas valve closed
What causes this fault?
This fault occurs when the boiler's internal sensors continue to detect a flame or electrical current after the heating cycle has finished and the gas should be turned off. The most common reason is a gas valve that is stuck open or leaking, though it can also be caused by a sensor that is damaged and sending a false signal to the control board.
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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A boiler cover plan would cover faults like FA306 — no call-out fees, no surprises.
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