232 / D3 Medium

Worcester Bosch 232 / D3 Fault Code

Also written as 232D3 — same fault.

The Worcester Bosch 232 / D3 fault code means: your boiler has been turned off by an external safety device, such as a thermostat, a service switch, or a smart heating controller.. It appears on 1 Worcester Bosch model 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: external cut-off switch activated
Typical repair cost £80-150 (including labour)

DIY fix possible

Check if any nearby electrical isolation switches for the boiler have been turned off by accident.Ensure your central heating thermostat or smart home controller is set to 'on' and that the battery is not dead.Verify that any external security or safety cut-off switches in your home haven't been tripped.

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Worcester Bosch models that show the 232 / D3 fault code

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

Source

Worcester Bosch 232 / D3 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