BoilerFaultCodesYour boiler detects a flame signal even though it has commanded the burner to turn off, which may be due to a faulty sensor or a sticking gas valve.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: An ionisation current was measured after the burner went out
What causes this fault?
This fault occurs when the boiler's internal safety sensors continue to detect a flame signal even after the unit has been told to stop burning gas. The most common reason is a faulty sensor or a sticking gas valve that isn't closing properly, posing a safety risk that requires the system to shut down immediately. Over time, moisture or carbon buildup on the electrodes can also cause the control board to 'see' a ghost signal that isn't actually there.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like FA306 — no call-out fees, no surprises.
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Worcester Bosch GB162 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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