Low
AM091 on Baxi 400 Combi 2

Your boiler is simply displaying a status message to indicate whether it is set to provide heating or just hot water, rather than reporting an actual fault.

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

Season mode (0: winter, 1: winter (antifreeze), 2: summer (neutral), 3: summer)

From this model's manual
Verified against the Baxi 400 Combi 2 installation & service manual, page 56.
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

Check your boiler control panel to see which mode is currently selected.Use the winter/summer button or dial to switch between heating and hot water settings as needed.Consult your user manual to confirm which code corresponds to your desired seasonal operation.

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