Low
6-tb on Worcester Bosch Greenstar 2000

Your boiler is currently running a self-diagnostic test to check the burner's performance across its full power range.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Burner test: 0...100%.

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for approximately 15 minutes for the test to complete automaticallyMonitor the display to see if it returns to the normal temperature readingIf the code persists for over an hour, try restarting the boiler using the reset button

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