How much does it cost to fix boiler error code 1021 B?

Typical repair cost for the boiler 1021 B fault is £90-160 including labour.

1021 B High

Boiler Fault Code 1021 B

Also written as 1021B — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 1021 B appears across 1 boiler brand and 11 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is unable to provide hot water because it cannot accurately measure how hot the water is. (As reported on Worcester Bosch Greenstar 8000 Life/Style)

Pick your boiler brand for the 1021 B fix

Worcester Bosch 1021 B 11 models

Source

Information for the 1021 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