BoilerFaultCodes A23 - A24 - A26 High
Boiler Fault Code A23 - A24 - A26
Also written as A23A24A26 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code A23 - A24 - A26 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler's electronic control system has detected that its internal settings have become corrupted or are incompatible, preventing it from operating safely. (As reported on Ferroli Bluehelix Tech RRT 24C)
Pick your boiler brand for the A23 - A24 - A26 fix
Source
Information for the A23 - A24 - A26 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026