BoilerFaultCodesYour boiler has lost its flame suddenly while it was running, causing it to stop heating your home 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: Loss of ionisation signal during operation
What causes this fault?
This fault occurs when the boiler’s control system suddenly loses the signal that confirms a flame is present while it is firing. The most common reason is that the flame is physically blowing out due to a gas supply issue, or the internal sensing probe has become too dirty or worn to detect the heat properly. It can also be caused by the boiler 'choking' on its own exhaust gases if there is a problem with the flue or air supply.
This fault is more common in winter, as frozen condensate pipes can cause backup issues that lead to a sudden loss of flame.
DIY fix possible
Check if other gas appliances like a hob are working to ensure you have a gas supplyCheck that your condensate pipe (outside) is not frozen during cold weatherPress the Reset button for five seconds and see if the boiler restarts
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like EA229 — no call-out fees, no surprises.
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Worcester Bosch CDi Classic 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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