BoilerFaultCodesTechnical 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 is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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