1010 O High

Worcester Bosch 1010 O Fault Code

Also written as 1010O — same fault.

The Worcester Bosch 1010 O fault code means: your boiler's internal computer has lost its connection to its main controls, meaning it cannot receive the instructions it needs to provide heating or hot water.. It appears on 10 Worcester Bosch models 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: No BUS communication cable, EMS-Bus isn’t connected or damaged – connect the cable for the EMS-Bus or replace the damaged cable exchange fuse

What causes the Worcester Bosch 1010 O fault?

This fault occurs when the boiler's central computer loses its physical connection to the internal wiring system that carries data commands. It is usually caused by a loose connection, a broken wire, or a blown fuse on the circuit board that prevents signals from reaching the vital components. Without this communication link, the boiler cannot receive instructions to fire up, even if the rest of the hardware is functioning correctly.

Typical repair cost £100-£250 (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 1010 O fault code

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

Source

Worcester Bosch 1010 O 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