Navien NP-180 Service Manual page 110

Check method
Error type Cause Check method
Defective contact
Check the assembly and contact of the gas pressure sensor connector.
of the connector
Defective
Check the gas pressure sensor input/output voltage.
sensor
Operating voltage (Black+Blue) : DC 5 V
Defective gas
Sensor output voltage (Black+White)
pressure sensor
Open : DC 0.1±0.1 V or lower
Short-circuit: DC 4.5±0.2 V or higher
<Check the GPS terminal>
Gas pressure
Check the assembly of the gas pressure (+) or (-) hose, and if there is
Gas pressure hose
hose is pulled
is pulled out
any damage on the hose.
out
If the trouble continues despite the checking of above items,
Defective
Other trouble
replace the PCB.
PCB
108
©Navien America Inc. 2010 NR/NP series service Manual Version 2.0