BoilerFaultCodesYour boiler is failing to detect a flame after several attempts, which means it has locked itself out for safety.
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 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.
DIY fix possible
Check if other gas appliances like a hob are working to ensure gas is reaching the propertyPress the 'Reset' button on the control panel to see if the boiler restartsIn freezing weather, check if the white plastic condensate pipe outside is frozen and thaw it with warm water
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like é5 — 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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