Boiler Fault Code 2966 B

Also written as 2966B — same fault.

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

Fault code 2966 B appears across 1 boiler brand and 14 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is heating up too quickly and has shut down to prevent damage, usually because water isn't flowing through the system fast enough. (As reported on Worcester Bosch Greenstar 8000 Life/Style)