Navien NP-180 Service Manual page 99

Check method
Error
Defective
temperature sensor
connector
Defective
sensor
Temperature
Defective
Other trouble
< Heat exchanger input temperature sensor /
connector, Black 2P >
©Navien America Inc. 2010
Cause
Check if the temperature sensor connector or the PCB harness
terminal is wet due to any reason, including leakage.
Check the resistance of the temperature sensor.
Replace the temperature sensor if the resistance value is abnormal.
sensor (Defective if it is 0.5
Check the temperature displayed on the PCB(C.10.0 10.0 ).
If the trouble continues despite the checking of above items,
replace the PCB.
PCB
97
NR/NP series service Manual
Check method
or lower)
< Check if the hot water tem-perature sensor is open >
Version 2.0