Medium
305 on Worcester Bosch 24 RSF

Your boiler thinks a hot water tap is still running and is waiting for it to be turned off before it can provide heating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

The boiler is waiting for domestic hot water (DHW) operation to end

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

Check all hot water taps in the house are fully turned offEnsure there are no dripping hot water taps or leaking shower headsTurn the boiler off and back on at the power switch to reset the sensor

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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 V235260265268270283284305 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 lightrET1T2T3T4T6

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