BoilerFaultCodesFerroli A23 Fault Code
The Ferroli A23 fault code means: your boiler has detected that the water inside the heating system is not flowing properly, which has triggered a safety shutdown to prevent the main heat exchanger from overheating.. It appears on 8 Ferroli models in our database.
Technical description: Exchanger protection intervention
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 A23 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ferroli A23 fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.
- Ferroli Arena 30 C manual (PDF)
- Ferroli Arena 30A manual (PDF)
- Ferroli Bluehelix HiTech RRT manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026