How much does it cost to fix Worcester Bosch error code 5.A?

Typical repair cost for the Worcester Bosch 5.A fault is £80-120 including labour.

5.A Low

Worcester Bosch 5.A Fault Code

Q: What does the Worcester Bosch 5.A fault code mean?

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

Also written as 5A — same fault.

The Worcester Bosch 5.A fault code means: your boiler is simply reminding you that its annual service is now due, and it does not indicate a breakdown or a safety fault.. It appears on 1 Worcester Bosch model in our database.

Technical description: Reset service reminder

What causes the Worcester Bosch 5.A 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.

Typical repair cost £80-120 (including labour)

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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Worcester Bosch models that show the 5.A fault code

Click a model for the full fault code list and model-specific repair notes.

Greenstar CDi Compact Repair: £80-120

Source

Worcester Bosch 5.A fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026