Boiler Fault Code Boiler sooting

Also written as BOILERSOOTING — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code Boiler sooting appears across 1 boiler brand and 4 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is not burning fuel efficiently, which is causing a dangerous build-up of soot and significantly increases the risk of carbon monoxide poisoning. (As reported on Ferroli Arean)