Worcester Bosch error codes
Common Worcester Bosch combi boiler fault codes and what they mean.
- 1017 W Water pressure too low
- 224 V Safety temperature limiter tripped
- 227 V No flame signal after ignition
- 9U 233 Heat control module (HCM) code plug faulty or disconnected
- A1 281 Pump stuck or running in air (little or no water in the system)
- B7 257 Internal error on the control board
- C1 264 Airflow stopped — the fan has stopped during operation
- C6 214 Fan not running
- C6 215 Fan running too fast
- C6 216 Fan running too slow
- CE 207 Low water pressure
- D1 240 Return temperature sensor wet or damaged
- D1 241 Return temperature sensor disconnected or damaged
- E2 222 Flow temperature sensor short circuit
- E2 223 Flow temperature sensor disconnected or damaged
- E5 218 Primary flow temperature too high
- E9 219 Heat exchanger overheated (safety limit reached)
- E9 224 Flue gas overheat — maximum thermostat activated
- EA 227 No flame detected after ignition
- EA 229 Flame lost during operation
- EA 234 Gas valve coil disconnected
- EA 261 Flame not established within the first seconds of ignition
- EA 338 Too many short burner starts — pump not detecting water
- EF 349 Flow and return temperature difference too large at minimum burner output
- F7 228 False flame — flame detected before the burner started
- FA 306 Flame detected after the burner stopped
- FD 231 Mains power interruption
- H11 Hot water outlet sensor defect
- H13 Annual service reminder