Chaffoteaux 10.iv Fault Code
Also written as 10IV — same fault.
The Chaffoteaux 10.iv fault code means: your boiler is struggling to move heat away from its internal workings, causing it to quickly turn on and off as it tries to protect itself from overheating.. It appears on 3 Chaffoteaux models in our database.
Technical description: Rapid cycling high/low or high/low/off - Blocked heat exchanger
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 10.iv fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Chaffoteaux 10.iv 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