How much does it cost to fix boiler error code FD 231?

Typical repair cost for the boiler FD 231 fault is £100-350 including labour.

FD 231 High

Boiler Fault Code FD 231

Also written as FD231 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code FD 231 appears across 1 boiler brand and 12 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 an unexpected interruption or irregularity in its electrical power supply, which has caused it to stop working for safety. (As reported on Worcester Bosch Junior 28i)

Pick your boiler brand for the FD 231 fix

Worcester Bosch FD 231 12 models

Source

Information for the FD 231 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