Low
DM019 on Baxi 400 Combi 2

Your boiler is simply showing its current hot water operational status, rather than indicating a 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

DHW mode active (0: OFF (antifreeze), 1: Reduced, 2: Comfort, 3: Antilegionella

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 display manual to confirm this is a status code rather than an errorNo physical intervention is requiredIf your hot water is working normally, you can safely ignore this display

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