Navien NFB Series User Manual

103Appendixes
12.3 Ladder Diagram
HOT NEUTRAL
Dual Venturi
Relay 3
Relay 5
Relay 6
Igniter
Speed Control
Primary
MCU 1
MCU 2
DC24V
WPS
APS
DC12V
DC15V
UART
Communication
Interface
CASCADE
(RS-485)
Fan
Hall Sensor
Exhaust
Thermistor 2
Heating Supply
Thermistor
Heating Return
Thermistor
Exhaust
Thermistor 1
System Supply
Thermistor
Zone2 Pump
FRONT PANEL
Communication
Interface
PWM
EMI
FILTER
DC9V
WD-PSS
SMPS
Primary
Secondary
3.15A
System Return
Thermistor
Outdoor
Thermistor
DHW Tank
Therminstor
Dip Switch
Air Handler
Output
LWCO
Relay 2
Zone1 Pump(DHW Tank)
Relay 1
Boiler Pump
Relay 4
Zone3 Pump(System)
5A
Zone1
Thermostat
Zone2
Thermostat
Zone3
Thermostat
DHW
Thermostat
R,W,C
R,W,C
R,W,C
R,W,C
DHW Priority
Output
Relay 7
Relay 8
Flame Rod
Relay 9
Zone Valve1
Relay 10
Zone Valve2
Relay 11
Zone Valve3
Linear
Trans
AC 24V
H.T.L(HE)
H.T.L(BH)
Gas Valve
Relay coil
1~11
DC5V
BLDC-FAN
Terminal Board
AC INPUT(AC 120VAC)
Terminal Board
20A
5A
5A
5A

Navien NFB Series Specifications

General

Brand	Navien
Model	NFB Series
Category	Boiler
Language	English