E33 High

Ferroli E33 Fault Code

The Ferroli E33 fault code means: your boiler has detected a communication error with its flue venting system, which means it will stop working to ensure your home remains safe.. It appears on 1 Ferroli 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: Flue sensor fault (short/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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Ferroli models that show the E33 fault code

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

Source

Ferroli E33 fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026