BoilerFaultCodes 2964 B High
Boiler Fault Code 2964 B
Also written as 2964B — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 2964 B appears across 1 boiler brand and 13 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 water is not moving through its internal heating unit fast enough, which can cause the system to overheat and shut down. (As reported on Worcester Bosch Greenstar 8000 Life/Style)
Pick your boiler brand for the 2964 B fix
Source
Information for the 2964 B 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