BoilerFaultCodes A01.23 High
Boiler Fault Code A01.23
Also written as A0123 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code A01.23 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 has detected that the fuel and air mixture used to heat your home is not burning correctly, so it has safely shut itself down to prevent unsafe operation. (As reported on Remeha Quinta Ace 30)
Pick your boiler brand for the A01.23 fix
Source
Information for the A01.23 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