BoilerFaultCodesTechnical description
internal fault
What causes this fault?
This fault occurs when the boiler's main control board suffers an internal electronic failure or a communication error between its components. It is often caused by a power surge, moisture getting onto the circuitry, or simply the electrical components wearing out over time. Because the 'brain' of the boiler can no longer safely manage the heating process, it shuts the system down as a precaution.
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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