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's control system cannot detect a steady flame after several attempts to fire up. The most common reason is a build-up of carbon or debris on the internal sensors, or a failure in the components that deliver the spark and gas to the burner.
This issue can sometimes appear during cold snaps if the external gas regulator freezes or if moisture affects the internal ignition components.
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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