Low
T1 on Worcester Bosch Greenstar 30i

Your boiler is currently running a self-diagnostic test to check if the ignition system is working correctly.

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

Ignition test – checking the igniter spark

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 test to complete automaticallyIf the code persists for more than a few minutes, try resetting the boiler by holding the reset button for five seconds

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Related fault codes

T2View →T3View →EAView →

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