Low
SF on Baxi Duo-tec Combi HE A

Your boiler is currently performing a self-check or calibration process to ensure it is running efficiently, which is a normal operational state.

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

Calibration Mode active (alternating with current boiler temperature)

From this model's manual
Verified against the Baxi Duo Tec Combi He A 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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