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Verified boiler fault-code guides
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Worcester Bosch · Greenstar Highflow CDi ErP
- Worcester Bosch b2Data error.
- Worcester Bosch b3Data error.
- Worcester Bosch b4Data error.
- Worcester Bosch b5Data error.
- Worcester Bosch b6Data error.
- Worcester Bosch d5Condensate pump fault.
- Worcester Bosch A7Hot water NTC sensor defective.
- Worcester Bosch E2CH flow NTC sensor defective.
- Worcester Bosch E9Safety temp. limiter in CH flow has tripped.
- Worcester Bosch U1Boiler flow temperature is too high; the boiler will shut down until it has cooled down.
- Worcester Bosch A1Pump dry run detection or pump running in air.
- Worcester Bosch A5Tank NTC defect.
- Worcester Bosch A8Break in communication to weather compensating clip-in control or Greenstar Comfort II RF (EMS communication error).
- Worcester Bosch b1Code plug not detected.
- Worcester Bosch d3External temperature limiter fault.
- Worcester Bosch d6Internal heat bank overflow.
- Worcester Bosch F0Internal error.
- Worcester Bosch F1ROM error check.
- Worcester Bosch FdReset button pressed by mistake.
- Worcester Bosch SEService required.
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