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.

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

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 →

All 93 fault codes on the 24 RSF

Seeing a different code? Every code this model can display, in one place.

2 pulses5 pulses9A 3629U 233200200 O201201 O202202 O203203 0204204 O208208 0212224 V226227 V228 V235260265268270283284305305 0306 V328356360360 V1010 O1017 W1021 B1022 B1037 W1065 B1068 W1073 W1074 W1075 W1076 W2920 V2924 V2925 V2927 B2946 V2948 B2950 B2963 B2964 B2965 B2966 B2967 B2970 B2971 BA1A7A8B1C6CC 800E2E9EAEA 227EA 229EA 261EF 349EH 258F0F2 1.25ATF7FAFA 306FA 364Fast flashFB 365FDFD 231Light offLight onNo lightrET2T3T4T6

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