Boiler Fault Code ALL 22

Also written as ALL22 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026

Fault code ALL 22 appears across 1 boiler brand and 3 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 temperature in one of your heating circuits has become dangerously high, so it has automatically shut down to prevent damage. (As reported on Sime Murelle Elite HE 35T System)