Low
Wrench symbol on Biasi Advance 25C

Your boiler is notifying you that it is due for its annual safety check and routine service.

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.

What the manual says

Manufacturer manual

Maintenance required (The wrench symbol is flashing without showing any error)

From this model's manual
Verified against the Biasi Advance 25c installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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