Low
6-t1 on Worcester Bosch Greenstar 2000

Your boiler is undergoing a diagnostic test where it attempts to spark repeatedly without releasing gas to check the ignition system.

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

Permanent ignition: Testing the ignition by means of permanent ignition without gas supply.

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 the testing cycle to complete automaticallyTurn the boiler off and back on again to reset the sequenceIf the code persists and the boiler won't fire, contact a professional

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