01Error - Navien NP-180 Service Manual

5.2. 01Error

Error occurrence conditions and check items
Error
In order to prevent boiling of the heat exchanger, if 208 (98
at the output of the heat temperature (or 194 (90 ) at the input of the heat
exchanger) for over 15 seconds, the system stops combustion. (In normal condition,
01E
the combustion is stopped by the output temperature of the heat exchanger.) If
Boiling
overheat is detected as the combustion is stopped, the system displays an error
message, and does not start combustion until the temperature goes below 185
(85 ) (or 176 (80 ) at the input of the heat exchanger).
(The error message "O1E" is cleared manually for the models before 324-5M.)
1. Check if the main heat exchanger is clogged.
2. Check the hot water output/input temperature sensor.
Check items
3. Check the controller DIP S/W capacity setting.
4. Check if the controller works properly.
Is the hot water thermistor
normal?
Yes
Check unit
©Navien America Inc. 2010
Description
No Replace hot water thermistor
Resistance between two red wires of CN 13 is from
0.8 to 20k ohm at normal condition.
Caution: Before measuring resistance of the thermistor,
remove the connector from the PCB.
65
NR/NP series service Manual
)or higher is sensed
Version 2.0