Chaffoteaux E 11 Fault Code
Also written as E11 — same fault.
The Chaffoteaux E 11 fault code means: your boiler is struggling to detect the flow of water through the system, meaning it cannot safely turn on to provide your heating or hot water.. It appears on 1 Chaffoteaux model in our database.
Technical description: Flow sensor open circuit
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 E 11 fault code
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Source
Chaffoteaux E 11 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