Low
DM009 on Baxi 400 Combi 2

Your boiler is currently in a setup or holiday mode rather than standard heating operation.

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

Primary operating mode (0: Programming, 1: Manual, 2: Antifreeze/Holiday)

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

Locate the mode selector or dial on the front control panel.Switch the setting from 'Programming' or 'Holiday' back to the 'Winter' or 'Summer' operating position.Check if the display returns to normal and the boiler fires up.

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