Navien NCB-180, Service Manual

Page: 109 / 149

106 NCB Service Manual Version 1.0
5.2.14 352Error
Error conditions and Check Items
Error Description
E352
High water
pressure
Upon receiving a signal from the water pressure sensor, the system displays the error(E352) on front panel.
High water level error if the water level of 56.6PSI or higher continues 3 seconds.
Error is automatically cancelled if water level is 43.5PSI or lower.
Check items
1. Check if the cold water pipe input water pressure sensor is wet due to any reason, including leakage..
2. Check the Auto Feeder Sensor
3. Check the controller
Check method
Fault Possible Causes Check method
E352 High water pressure
Check the pressure increase conditions. (high water pressure of 3.9bar or higher)
Check if the safety valve is stuck.
Check if Auto feeder valve is normal.
High water
pressure sensor
Defective water
pressure sensor
1. Check the output voltage. (Normal state : 0.3~2.8V)
2. Replace the defective or opened water pressure sensor.
Defective Auto
Feeder valve
1. Check the Auto feeder valve. (refer to page76)
NO
Yes
Leaking in unit
Check leaking in unit
1. Check connecter
(#1,#2 and #3 of CN 22)
Is the water
pressure sensor
normal?
Yes
Replace the water pressure sensor
NO