Low Service
5.A on Worcester Bosch Greenstar CDi Compact

Your boiler is simply reminding you that its annual service is now due, and it does not indicate a breakdown or a safety fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

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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Related fault codes

H13View →9AView →

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