BoilerFaultCodesTechnical description
Internal fault when testing the ionisation signal
What causes this fault?
This fault occurs when the boiler's internal computer fails to properly monitor the electrical signal produced by the flame. The most common reason is a build-up of carbon on the sensing probe or a loose connection in the wiring that prevents the system from confirming the boiler is burning gas safely. In some cases, it can also be triggered by a glitch in the main circuit board itself.
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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