046Error - Navien NHB-055 Service Manual

5.2.7 046Error

Error occurrence conditions and check items
5.2.8 047Error
Error occurrence conditions and check items
100 NHB Service Manual
Is heat exchanger
thermistor normally
operating?
No
Is resistance within
normal range?
(refer to page 67)
No
Replace heat exchanger
thermistor.
Is exhaust thermistor
operating normally?
Yes
Check connector
(#1 and #2 of CN13)
Yes
Check connector
( #7 and #8 of CN 13)
1 step: Flushing, Clean Filter
Yes
2 step: Try to restart
3 step: Replace PCB
No
Replace exhaust thermistor
Resistance between #9 and #10 of CN13
is from 2kΩ to 300kΩ at normal condition.
(see page 63-64 for Wiring Diagram)
Version 1.0