BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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