BoilerFaultCodesYour boiler's internal computer brain has developed a critical fault and is unable to manage the system safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control box failure
What causes this fault?
This fault occurs when the boiler's main electronic circuit board suffers a hardware failure or a memory error, preventing it from processing safety data. It is often caused by long-term heat exposure degrading the electrical components or a sudden power surge that damages the sensitive microprocessors. Effectively, the boiler can no longer trust its own internal instructions and shuts down to prevent an accident.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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