Your boiler is working normally, but it is providing a friendly reminder that its annual safety and maintenance service is now due.

The appliance has a service reminder - please contact your service engineer.

What causes this fault?

This is not a mechanical failure, but a timer-based notification triggered by the control board. It occurs because the boiler has reached a specific interval of internal operating hours or a set calendar date since its last professional inspection. The system uses this feature to ensure the appliance continues to run safely and efficiently by prompting a scheduled check-up.