Technical description
Service timer function
What causes this fault?
This notification is triggered by an internal clock within the boiler’s control board that tracks the time elapsed since its last professional maintenance check. It is not caused by a mechanical failure or a parts breakdown, but rather a pre-set countdown reaching its limit. Once the timer completes, the display shows this code to prompt you to book a Gas Safe engineer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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