BoilerFaultCodesYour boiler has detected an internal computer error that is preventing it from starting up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: A flashing indicator shows a failure in the electronic boards.
What causes this fault?
This fault occurs when the internal computer boards responsible for managing the boiler's operations lose the ability to communicate with each other correctly. The most common reason is an electrical component failure or a short circuit within the control box that prevents the system from performing its safety checks. Because the boiler can no longer verify its own sensors, it shuts down instantly to prevent any dangerous operation.
This fault is more common following summer or during heavy storms, as electrical surges from lightning or moisture buildup during long periods of inactivity can damage sensitive circuit boards.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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