ao-smith NNLP-110-H NG Tankless Water Heater Error Codes
NNLP-110-H NG Error Code Reference
Section titled “NNLP-110-H NG Error Code Reference”Natural gas, 6 GPM
| Error Code | Fault Description |
|---|---|
| E1 | No ignition — burner failed to light |
| E5 | Insufficient water flow or flow sensor fault |
| E7 | Exhaust / flue blockage or temperature sensor fault |
| E11 | Cold inlet thermistor (NTC1) fault |
| E10 | Combustion air fan motor fault |