BoilerFaultCodesTechnical description
Internal fault
What causes this fault?
This fault occurs when the boiler's internal computer chips stop talking to each other correctly. It is usually caused by electrical components on the main control board wearing out or becoming unstable due to age. In some cases, loose or damaged wiring between the internal sensors and the brain of the boiler can also trigger this specific error.
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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