Low
H.02.00 on Baxi 400 Combi 2

Your boiler is currently restarting itself and you simply need to wait a moment for the system to finish its startup sequence.

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

Reset in progress

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

Wait approximately 1-2 minutes for the code to clear automaticallyCheck if the display returns to the normal temperature readingEnsure the boiler power hasn't been switched off and on again accidentally

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