What the manual says
Manufacturer manualPower up mode. Appliance is initialising.
From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Greenstar 12i System installation & service manual, page 63.
DIY fix possible
Wait 5 minutes to allow the boiler to complete its automated startup sequence.If the code persists, perform a system reset by holding the reset button for 3 seconds.If it still does not return to normal operation, switch the boiler off at the fused spur for 1 minute and turn it back on.
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All 224 fault codes on the Greenstar 12i System
Seeing a different code? Every code this model can display, in one place.
8C8E9A9A 3629U9U 233112113114115200201202203204205207208210211212213214215216217218219220221222223224225227228229230231232233234237238239240241256257258259260261261 EA262263264264 C1265266266 CE267267 F0268269269 EA271271 D4272272 F0273273 C4274276276 E9277277 E9278278 F0279279 F0280280 F0281281 A1282282 H5283284285285 E9286286 D1287287 F0288288 CF289289 CF290290 F0305306306 FA307308309310311312313314315316316 E9317317 A3318318 E9321322323323 A8324325326327328329332333338341342343344345346347348349350351353354357358359364365372373374375376380800808810828A1A1 281A3A7A8ACb1b7b7 257Blue lightBlue light onC1C1 264C4C4 273C6C6 215C7C7 214CECFD1D1 240d3D4D4 271E2E2 222E3E4E5E5 218E9E9 219E9 224EAEA 227ECEDEFEF 349F0F7F7 228FAFA 306FA 364Fast flashing reset buttonFbFb 365FdFD 231Flue overheatH5H11H13i01i02LOCKOUTOn / OffReset Button IlluminatedSlow flash (normally off)Slow flashing reset button