Low
T1 on Worcester Bosch 24 RSF

Your boiler is currently running a self-diagnostic check to see if it can create the spark needed to light the burner.

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.

Technical description

Ignition test – checking the igniter spark

DIY fix possible

No action required; this is a normal self-test sequenceWait for the boiler to finish its diagnostic checkIf the code persists or turns into a fault, try resetting the boiler

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Related fault codes

T2View →T3View →EAView →

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