Low
208 on Worcester Bosch Greenstar 8000 F GR8700iF 35 R

Your boiler is currently set to a manual testing mode used by engineers to check emissions, which prevents it from operating normally.

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

Chimney sweep demand

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.

DIY fix possible

Locate the 'Chimney Sweep' button (icon looks like a brush) on the touch screen display.Press and hold the button for approximately 3 to 5 seconds.The display should return to the standard temperature screen once the mode is deactivated.

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Related fault codes

200View →201View →

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 O203204214224227228229232233234235237238242244244 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 V2948 B2949 B2950 B2951 V2952 V2955 B2956 O2957 V29612961 V2962296329652966297229802981

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