Navien NCB-150E Service Manual page 89

Failure mode
Other trouble
88 NCB-E Service Manual
Cause
Sudden increase of temperature due to PCB DIP S/W model setting error or max setting.
Capacity setting
Defective PCB If the trouble continues despite the checking of above items, replace the PCB.
Check method
Capacity
150,000 BTU (180)
175,000 BTU (210)
199,000 BTU (240)
120,000 BTU (150)
DIP S/W No.
5 6
OFF OFF
ON OFF
OFF ON
ON ON
Version 1.4