A23 - A24 - A26 High

Ferroli A23 - A24 - A26 Fault Code

Also written as A23A24A26 — same fault.

The Ferroli A23 - A24 - A26 fault code means: your boiler's electronic control system has detected that its internal settings have become corrupted or are incompatible, preventing it from operating safely.. 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: PCB parameter fault
Typical repair cost £200-450 (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 A23 - A24 - A26 fault code

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

Source

Ferroli A23 - A24 - A26 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 7 July 2026