Low
SF on Baxi Duo-tec Combi

Your boiler is currently running a brief self-diagnostic calibration test, which is a normal process after recent adjustments or a power cycle.

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

Calibration Mode active (alternating with current boiler temperature)

Engineer required

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

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