BoilerFaultCodesYour boiler has encountered a computer failure and has gone into a safety shutdown mode, meaning you will have no heating or hot water until it is repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal fault. Possible solution/check: Replace control board
What causes this fault?
This fault occurs when the boiler's internal computer, the Printed Circuit Board, suffers a critical communication failure or an electrical short circuit. It is often caused by general wear and tear of the electrical components over time or a sudden power surge that damages the sensitive microprocessors. Because the 'brain' of the boiler can no longer safely monitor the heating process, it shuts everything down as a protective measure.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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