BoilerFaultCodesYour boiler's internal computer parts are having trouble communicating with each other, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Software incompatibility
What causes this fault?
This fault occurs when the boiler's internal control boards are unable to 'talk' to each other, often after a component has been replaced or due to a memory error. It physically happens because the software version on the main circuit board does not match the version on the display panel, leading the boiler to shut down as a safety precaution. The system effectively becomes confused and stops working because it cannot verify that the internal instructions are consistent across all parts.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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