Fault 01 / 200 High

Worcester Bosch Fault 01 / 200 Fault Code

Also written as FAULT01200 — same fault.

The Worcester Bosch Fault 01 / 200 fault code means: your boiler's internal computer has lost communication with its control components, meaning it cannot receive or send the signals needed to operate.. 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: BUS communication fault: Boiler no longer reporting.

What causes the Worcester Bosch Fault 01 / 200 fault?

This fault occurs when the boiler's main brain and its internal components stop talking to each other, often due to an electrical interruption or a fried component. The most common reason is that the main control board has suffered a critical failure, though it can also be caused by loose or damaged wiring inside the unit.

Typical repair cost £180-450 (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 Fault 01 / 200 fault code

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

Source

Worcester Bosch Fault 01 / 200 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