Worcester Bosch 231 / FD Fault Code
Also written as 231FD — same fault.
The Worcester Bosch 231 / FD fault code means: your boiler has detected a disruption in its electrical supply, which has caused it to temporarily shut down the system.. It appears on 1 Worcester Bosch model in our database.
Technical description: Mains power error - electrical power interruption
DIY fix possible
Check that your boiler's power supply switch is turned onIdentify and reset your boiler's circuit breaker in your home's consumer unitPress the 'Reset' button on the front of your boiler control panel
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Gas Safe Register →Worcester Bosch models that show the 231 / FD fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch 231 / FD fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026