BoilerFaultCodesChaffoteaux 23 Fault Code
The Chaffoteaux 23 fault code means: your boiler is struggling to breathe because the internal fan that moves air through the system is not spinning fast enough to light or maintain the flame safely.. It appears on 6 Chaffoteaux models in our database.
Technical description: Fan speed too low
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 23 fault code
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Source
Chaffoteaux 23 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