29 Medium

Baxi 29 Fault Code

The Baxi 29 fault code means: your boiler has detected an issue with the sensor that monitors the temperature of the water used for your radiators, causing the heating to stop working correctly.. It appears on 5 Baxi models in our database.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description: Fault on Central Heating Sensor
Typical repair cost £90-160 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Baxi models that show the 29 fault code

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

Source

Baxi 29 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 27 April 2026