Ariston E11 Fault Code
The Ariston E11 fault code means: your boiler is failing to detect that water is moving through the system, meaning it won't start up to provide you with heating or hot water.. It appears on 2 Ariston models 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 →Ariston models that show the E11 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ariston E11 fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026