Navien error code 353

E353 Abnormal water pressure sensor

If an error (under 0.3V or over 2.8V) in the water pressure sensor is detected continuously for 3 seconds, The system displays the error message E353 on the front panel. If this occurs, the boiler initiates shutdown.

Check items

  1. Check if the cold water pipe input water pressure sensor is wet due to any reason, including leakage..
  2. Replace the water pressure sensor
  3. Check the controller