Fault 01 Code 200 — BUS communication fault, boiler not reporting

What does Fault 01 200 mean?

The Worcester Bosch Greenstar CDi Boiler displays Fault 01 with code 200, indicating a communication issue on the BUS system where the boiler is no longer reporting its status to the controller.

• Faulty BUS device
• Loose or damaged BUS connection cable
• Circuit break in the BUS wiring

Click steps to track your progress.

1. 1

   Check all visible BUS connections for looseness or damage.

2. 2

   Ensure all BUS devices are correctly connected and powered.

3. 3

   If connections appear sound, contact a qualified heating engineer to inspect the BUS device or wiring for a circuit break.