E 11 High

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.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Flow sensor open circuit
Typical repair cost £150-250 (including labour)

Engineer required

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

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Chaffoteaux models that show the E 11 fault code

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

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