11 High

Baxi 11 Fault Code

The Baxi 11 fault code means: your boiler is currently set to provide hot water but is failing to communicate correctly with your heating controls or hot water cylinder, meaning the system cannot complete the request to heat your water.. It appears on 7 Baxi models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Hot Water Mode
Typical repair cost £120-250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Baxi models that show the 11 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Baxi 11 fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026