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Worcester Bosch Greenstar 2000 Combi

200 Boiler in heating mode 201 Boiler in hot water mode 202 Boiler in anti-cycle mode 203 Boiler in standby, no heat energy demand 204 Current prim. water temp. higher than set val. 208 Chimney sweep demand 212 Rise in temp. of safety or heating flow sensor too fast 214 Fan shut down during safety time 215 Fan shut down during safety time 224 Safety temp. limiter has tripped 227 No flame signal after ignition 228 Flame signal without flame present 229 Flame failed during burner operation 232 Boiler locked by external switching contact 233 Boiler identification module or device electronics faulty 234 Gas valve electrical fault 235 Conflicting versions of boiler electr. and boiler identification 237 System fault 238 Boiler electronics faulty 242 Boiler electr. system fault 244 System fault boiler electronics / basic controller 245 State out of range 246 System fault boiler electronics / basic controller 247 System fault boiler electronics / basic controller 249 Internal software error 250 Default software error 251 Flash test error 252 Stack overflow 253 RAM test error 254 Eeprom test error 256 System fault boiler electronics / basic controller 257 System fault boiler electronics / basic controller 258 Internal watchdog error 259 AD reference error 262 Internal OS error 263 Program sequence error 264 Air handling failed during operation 265 Heat demand lower than energy supplied 268 Relay test was activated 269 Flame monitoring 270 Starting up boiler 273 Operation of burner and fan interrupted 275 Boiler electronics in test mode 281 Pump pressure increase too low 283 Burner starting 284 Opening air/gas ratio control valve/oil solenoid valves 305 Boiler in hot water anti-cycle mode 306 Flame signal after closing the fuel supply 323 BUS signal cannot be processed 328 Brief mains voltage failure 341 Temperature rise at boiler too rapid 342 Temperature rise during hot water mode too rapid 350 Short-circuit at flow temp. sensor 351 Flow temp. sensor interrupted 353 Test non-volatile lockout 354 Test volatile lockout 356 Power supply for the boiler is too low 357 Ventilation program 358 Anti-seizing functn. active 360 Incomparable code plug 362 Boiler identification module or boiler electronics faulty 363 Ionisation current did not drop during ionisation test 364 Solenoid valve ev2 leaking. 365 Solenoid valve ev1 leaking. 604 System fault burner control unit 810 Hot water remains cold 1010 No BUS communication 1013 Max. combustion point reached 1014 Actual ionisation is too low 1018 Maintenance interval expired 1019 Incorrect pump type detected 1021 Cylinder charging or hot water temperature sensor faulty 1023 Maximum run time including standby time reached 1025 Return temp. sensor is faulty 1027 DHW pre-heat kit inlet sensor is disconnected 1037 Outside temp. sensor faulty - heating back-up operation active 1068 Outside temp. sensor or lambda probe faulty 1073 Short circuit of the flow temperature sensor 1074 No signal from flow temperature sensor 1075 Short-circuit heat exchanger temperature sensor 1076 No signal from heat exchanger temperature sensor 2051 Internal fault 2085 Internal fault 2908 System fault boiler electronics/basic controller 2910 Error in the flue gas system. (Too much or too little resistance in air flow) ▶ the fan speed is higher than expected due too missing exhaust. ▶ the fan speed is to low due to an obstruction in the exhaust. 2911 Calibration failed 2912 No flame signal during calibration 2913 Flame signal too low during calibration 2914 There is no communication between the appliance controller and burner module 2915 The fan keeps running after the post purge 2916 Gas valve was detected to be open during post purge 2917 No flame signal when checking the combustion control 2918 Fault in combustion control 2920 Fault in flame monitoring 2921 Boiler electr. in test mode 2922 Internal fault 2923 Unexpected feedback from the modulating/ current controlled gas valve 2924 No feedback from the gas valve 2925 Too low feedback from the modulating gas valve 2926 Too high feedback from the modulating/ current controlled gas valve 2927 Flame failed during burner operation 2928 Internal error 2930 System fault boiler electronics / basic controller 2931 Illegal instruction executed by microcontroller 2932 System fault boiler electronics / basic controller 2940 Low voltage 2941 Insuff. flow rate in boiler 2942 No speed feedback signal from fan 2943 Mains voltage too low 2945 Too many short heat demands in short time h 2946 Incorrect code plug detected 2947 Incorrect code plug detected 2948 No flame signal with low output. 2949 No flame signal with high output. 2950 No flame signal following starting procedure 2951 Loss of flame too many times 2952 Internal fault when testing ionisation signal 2953 No flame signal with low output. 2954 No flame signal with high output. 2955 Boiler does not support the parameters set for the hydraulic configuration 2956 Hydraulic configuration at the boiler activated 2957 Internal burner control error 2958 System fault, appliance electronics. 2959 System fault, appliance electronics. 2960 System fault, appliance electronics. 2961 No fan signal available 2962 Fan not running 2963 Signal from flow and heat exchanger temperature sensor outside the permissible range 2964 Flow rate in heat exchanger too low 2965 Flow temperature too high 2966 Flow temperature rise in heat exchanger too rapid 2967 Flow/heat exchanger temperature sensor differential too great 2971 System pressure too low 2972 Mains voltage too low 2973 System fault boiler electronics / basic controller 2974 Internal fault 2981 Locking fault (Boiler locked. Contact a qualified heating engineer) 3071 Comfort + II RF Combustion noises too loud; rumbling noises. Faults that are not displayed Heat-up takes too long. Faults that are not displayed Flue gas values incorrect; CO content too high. Faults that are not displayed Delayed ignition, poor ignition. Faults that are not displayed Condensate in air box. Faults that are not displayed No hot water. Faults that are not displayed DHW volume is not reached Faults that are not displayed No function, the display remains dark Faults that are not displayed
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