BoilerFaultCodes Anti-frost device Low
Boiler Fault Code Anti-frost device
Also written as ANTIFROSTDEVICE — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Anti-frost device 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 water inside is getting too cold and has automatically turned on its internal heater to prevent the pipes from freezing. (As reported on Ariston Excalibur)
Pick your boiler brand for the Anti-frost device fix
Source
Information for the Anti-frost device 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 27 April 2026