231 Medium

Worcester Bosch 231 Fault Code

The Worcester Bosch 231 fault code means: your boiler has detected a brief loss of electricity or a dip in power, causing it to shut down temporarily.. It appears on 2 Worcester Bosch models in our database.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description: FD Mains power error - electrical power interruption
Typical repair cost £80-150 (including labour)

DIY fix possible

Check that your boiler's power supply switch is turned onCheck your home's fuse box to ensure the boiler's circuit breaker has not trippedPress the reset button on the boiler's front panel to see if it restarts

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Worcester Bosch models that show the 231 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch 231 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 31 August 2026