BoilerFaultCodesYour boiler has lost its unique configuration settings and currently thinks it is a blank unit from the factory.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Factory setting
What causes this fault?
This fault occurs when the boiler's internal memory has been wiped or corrupted, meaning the unit has forgotten its specific model and power settings. It is usually caused by a major electrical surge or a failure in the main control board that erases the vital 'Device Specific Number' needed for operation. Without this digital identity, the boiler shuts down as a safety precaution because it no longer knows how to manage its gas and water flow safely.
This fault is more common during winter or stormy weather, as power surges and lightning strikes are more frequent and can damage the boiler's sensitive electronic components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like D.96 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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