BoilerFaultCodesYour boiler has detected an internal computer error and has stopped working for safety reasons.
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. Replace control board.
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure, meaning the 'brain' of the appliance can no longer process instructions safely. It is usually caused by electrical components wearing out over time or damage from a sudden power surge. Because the board can no longer verify that the boiler is operating correctly, it shuts the system 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.
Gas Safe Register →Protect yourself from future repair bills
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