BoilerFaultCodesYour boiler has experienced a fundamental software or memory error that has caused it to shut down securely 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: Non-volatile lockout
What causes this fault?
This fault occurs when the boiler's internal memory experiences a critical failure, meaning the control board can no longer read or store the essential settings needed to run safely. It is usually caused by a physical hardware malfunction within the circuitry or an electrical surge that has corrupted the software components. Because the 'brain' of the boiler can no longer verify its own safety checks, it enters a permanent shutdown to prevent any unpredictable behavior.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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