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Wrench symbol flashing on Biasi Advance Plus 16S 25S 30S

Your boiler is simply reminding you that its annual service interval has been reached and it is due for a routine professional check-up.

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

From this model's manual
Verified against the Advance Plus Erp Service 2018 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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