BoilerFaultCodesTechnical description
Internal control box error
What causes this fault?
This fault occurs when the boiler's main control board experiences a critical internal communication failure or electronic glitch. It essentially means the 'brain' of the boiler can no longer verify that its safety systems are functioning correctly, so it shuts down as a precaution. The most common reason is the natural degradation of the electrical components on the circuit board over time.
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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