7.5 High

Baxi 7.5 Fault Code

Also written as 75 — same fault.

The Baxi 7.5 fault code means: your boiler is experiencing a communication error between its internal electronic parts, meaning it has stopped working until the settings are correctly synchronised.. It appears on 1 Baxi model 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: Conversions
Typical repair cost £150-300 (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 7.5 fault code

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

Source

Baxi 7.5 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