Low
H.02.09 on Baxi 400 Combi 2

Your boiler has detected very low temperatures and is automatically running its frost protection mode to prevent the internal pipes from freezing.

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

Partial stoppage — antifreeze function active

From this model's manual
Verified against the Baxi 400 Combi 2 installation & service manual, page 70.
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 that your main gas and electricity supplies are still turned onEnsure your thermostat is turned up or the boiler is not in 'off' modeCheck for any frozen sections of the condensate pipe outside your home and thaw them with warm water

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