BoilerFaultCodesYour boiler is simply reminding you that its annual service is now due, and it does not indicate a breakdown or a safety fault.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Reset service reminder
What causes this fault?
This code appears because a pre-set timer, calibrated by your heating engineer during their last visit, has reached its annual limit. It is not triggered by a mechanical failure, but rather by the boiler’s internal clock reaching the 12-month interval for professional maintenance. Once this threshold is met, the display alternates between the temperature and this code to prompt you to book a safety check.
DIY fix possible
Press and hold the 'Reset' button for approximately five seconds.The display should clear and return to the standard temperature output.Contact a Gas Safe registered engineer to book your annual maintenance service.
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