1009 B High

Worcester Bosch 1009 B Fault Code

Also written as 1009B — same fault.

The Worcester Bosch 1009 B fault code means: your boiler's internal pump is not communicating correctly with the main control board, meaning the system cannot circulate hot water around your home.. It appears on 1 Worcester Bosch model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Pump communication failure or wrong pump is fitted (non-ErP).
Typical repair cost £220-450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Worcester Bosch models that show the 1009 B fault code

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

Source

Worcester Bosch 1009 B 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