BoilerFaultCodesYour boiler has tried to light several times but cannot confirm that a flame has been successfully established.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical 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.
DIY fix possible
Check that your gas emergency control valve is open and other gas appliances are working.Ensure your condensate pipe (the white plastic pipe outside) hasn't frozen in cold weather.Press the 'Reset' button on the boiler control panel for two seconds.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like e5 — no call-out fees, no surprises.
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Remeha Avanta 18V 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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