BoilerFaultCodesYour boiler’s internal computer has encountered a critical error and can no longer control the heating 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: General PC board fault
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure or a memory corruption, leaving it unable to process instructions. It is usually caused by electrical wear over time or a sudden power surge that damages the delicate electronic components inside the unit. In some cases, loose or damaged wiring connections between the board and the rest of the boiler can also trigger this error.
This fault is slightly more common during the winter months when the boiler is under constant load and electrical components are more susceptible to failure during power fluctuations caused by stormy weather.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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