BoilerFaultCodesTechnical description
No ionisation or ionisation failure more than 5 times during one heat demand.
What causes this fault?
This fault occurs when the boiler tries to light the gas but cannot detect a steady flame to confirm it is safe to continue. The most common reasons are worn-out sensors that can no longer 'see' the flame, a faulty ignition spark, or an issue with the gas supply preventing the burner from firing up correctly.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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