BoilerFaultCodesTechnical 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.
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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