Chaffoteaux 29 Fault Code
The Chaffoteaux 29 fault code means: your boiler is stuck in heating mode, which means your radiators might stay hot even when you only want hot water, or you may find you have no hot water at all.. It appears on 6 Chaffoteaux models in our database.
Technical description: Three way valve blocked in CH mode
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Chaffoteaux models that show the 29 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Chaffoteaux 29 fault code information on this page is sourced and cross-checked against the official Chaffoteaux service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026