Navien NR-180 Installation Manual page 64

Gas Water Heater Installation
█ Ladder Diagram:
NP
HOT NEUTRAL
120VAC
Power
Switch
Transformer
AC150V
AC19V
AC26V
DC5V
AC9V
Flow Sensor
APS
GPS
Fan
Hall Sensor
Water Leakage
Detection
H/E
Thermostat
C/W
Thermostat
H/W
Thermostat
High Limit S/W
Exhaust Limit S/W
.
64
Relay 1
Relay 2
Relay 3
Relay 4
Relay 6
Relay 9
Primary
Mixing Valve
Mixing Control
Secondary
FAN
DC15V
Speed Control
Water Adjustment
DC24V
Valve
Flow Control
Flame rod
WD-RSS
Modulation
GV
Relay Power Supply
MCU 1
Driving Circuit
Relay 1
Remote Controller
Interface
MGV
SGV 1
SGV 2
Igniter
2-Way V/V
MCU2 Pulse
Signal
MCU 2
Relay 2
Relay 3
Relay 4
Relay 6
Relay 9
Remote
Ready Link
Ready Link
Controller
Interface