BoilerFaultCodesYour boiler’s internal computer has encountered a critical communication error and cannot operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal boiler control error
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure and can no longer communicate with the internal sensors. It is usually caused by electrical components on the circuit board wearing out over time or a loose connection in the internal wiring loom. Because the 'brain' of the boiler can no longer monitor safety, it shuts the entire system down as a precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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