Ariston E33 Fault Code
The Ariston E33 fault code means: your boiler has detected that the internal components responsible for venting waste gases are not working correctly, causing the system to stop for safety reasons.. It appears on 7 Ariston models in our database.
Technical description: Fan error. Check the fan cable, replace the fan, or replace the main P.C.B.
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 E33 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ariston E33 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