BoilerFaultCodesTechnical description
Internal error - replace control board
What causes this fault?
This fault occurs when the boiler's main control board experiences a persistent data error or a physical failure in its electronic circuitry. It is essentially a communication breakdown between the boiler's Brain and its components, often caused by age-related degradation of the circuit board or a sudden electrical surge.
This fault can sometimes follow heavy summer storms, as power surges or nearby lightning strikes are known to damage sensitive electronic control boards.
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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