Technical description
Maintenance is now due please call your service engineer
What causes this fault?
This code is triggered by the boiler's internal timer reaching a pre-set limit of operating hours or months since its last professional inspection. It is not caused by a mechanical failure, but rather a deliberate reminder programmed by your engineer to ensure the appliance remains safe and valid under warranty. The code will remain visible until a qualified professional performs the service and resets the maintenance counter.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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