Operation Flow Chart - Navien NPE-180A Service Manual

4.2 Operation Flow Chart

20 NPE Service Manual
120v Power
Applied
System
Displays version
Initialization
NO
Standby Mode
Flow sensor
≥ 0.53 gpm
Yes
Fan start-up &
Fan control
IG ON
MGV1 ON
MGV2 ON
NO
Stage 1 or
Stage 2 ?
Dual venturi OFF
NO
Flame ON?
Yes
IG OFF
Burner Operation
NO
IG : Igniter
MGV1 : Main Gas valve 1
MGV2 : Main Gas valve 2
Stage 2
Stage 1
Dual venturi ON
Flame check time
> 3 sec
Flow sensor
≤ 0.48 gpm
Yes
MGV1 OFF
MGV2 OFF
Post Purge
Fan Stop
Yes
Version 2.21