Low
SF on Baxi Platinum Combi

Your boiler is not broken; it is simply running a self-test or calibration cycle which usually happens after a restart or during commissioning.

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 / Startup function (alternating with current boiler temperature)

From this model's manual
Verified against the Baxi Platinum Combi 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.

DIY fix possible

Wait up to 20 minutes for the calibration cycle to complete automatically.Do not turn the boiler off while the SF code is flashing.Check if any hot water taps are running and turn them off to allow the process to finish.

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