Medium
2948 B on Worcester Bosch Greenstar 8000 F GR8700iF 35 R

Your boiler temporarily failed to detect a flame during a low-power start, often caused by strong outside winds blowing down the flue.

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

No flame signal with low output: Burner starts automatically after purging. This can be caused by strong winds.

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Wb 47850 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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

2948View →EAView →D7View →

All 99 fault codes on the Greenstar 8000 F GR8700iF 35 R

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

200 O201201 O202202 O203204208214224227228229232233234235237238242244244 V245 V246 V247 V248 V249 V250 V251 V252 V253 V254 V257 V258 V259 V262 V263 V265 B268 O269 V273 B281 B283 O284 O306 V357 O358 O360 V362 V363 V604 V815 W1010 O1013 W1018 W1019 W1022 W1023 W1025 W1037 W1068 W1070 W1071 W1072 W1075 W1076 W2085 V2908 V2910 V29142915 V2916 V2920 V2923 V2924 V2925 V2926 V2927 V2928 V2931 V2940 V2946 V2949 B2950 B2951 V2952 V2955 B2956 O2957 V29612961 V2962296329652966297229802981

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