BoilerFaultCodesTechnical description
When the boiler has run for more than 1 year.
What causes this fault?
This is not a mechanical failure but a built-in timer notifying you that 12 months have passed since the last maintenance visit. The boiler tracks its own run-time and calendar days to ensure vital safety checks and cleaning are performed by a professional on schedule.
This notification often appears in autumn as homeowners turn their heating back on for the first time, triggering the completion of a full annual cycle.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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