Low
12 on Saunier Duval Xeon 120 FF

Your boiler is currently in a special setting mode used by engineers to calibrate the airflow, rather than experiencing a standard mechanical failure.

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

Fan speed reduction to minimum during service potentiometer adjustment / LPG conversion

From this model's manual
Verified against the Saunier Duval Xeon 120 Ff 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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