Error - Navien NCB-24LSWE Service Manual

5.2.14 Error 302

Error conditions and checklist
Error
Low pressure faults are monitored by a water pressure sensor and when a fault is detected the system
E302
displays 'E302' Low water level error is generated if water pressure is 0.5 bar or less for 3 sec.
Low water
The error is automatically cancelled if water pressure returns to 0.5 bar or above.
pressure
1. Check if the input water pressure sensor is wet for any reason, including leakage.
Checklist
2. Check the auto feeder.
3. Check the controller
Testing method
Fault Possible causes
E302 Low water pressure
Low water Water pressure
pressure sensor
108 NCB Service Manual
Check the water supply pressure (0.5 bar or lower is the error state).
Check if the safety valve is stuck.
1. Check the output voltage. (Normal state: 0.25-- 4.93 V)
sensor fault
2. Replace the faulty or open water pressure sensor.
Description
Testing method
Version 1.0