Ladder Diagram - Navien NFB-175H Installation Manual

12.3 Ladder Diagram

VID
APS
Exhaust
Thermistor 1
Heating Supply
Thermistor
System Supply
Thermistor
Outdoor
Thermistor
Linear
Trans
AC 24V
O O
N N
1 2 3 4 5 6 1 2 3 4 5 6 7
Dip Switch
Zone1 Thermostat
Zone2 Thermostat
Zone3 Thermostat
DHW Thermostat
Relay 9
Relay 10
Relay 11
AC INPUT(AC 120V)
LIVE NEUTRAL
EMI
FILTER
PWM
Primary Primary
SMPS
Secondary
DC15V
DC24V
DC12V
WPS
Fan
Hall Sensor
Exhaust
Thermistor 2
Heating Return
Thermistor
System Return
Thermistor
MCU 1
DHW Tank
Thermistor
8 LWCO
R,W,C
R,W,C
R,W,C
R,W,C
Zone Valve 1
Zone Valve 2
Zone Valve 3
Dual Venturi
Relay 5
Relay 6
Ignitor
Speed Control
Fan
DC9V
DC5V
H.T.L(HE)
H.T.L(BH)
WD-PSS
Gas Valve
Communication
Interface
UART
Communication
Interface
CASCADE
(RS-485)
Terminal Board
Air Handler
DHW Priority
AC INPUT(AC 120 V)
LIVE NEUTRAL
Terminal Board
Relay 1
10A
Boiler Pump
Relay 2
10A
ZONE1 Pump
(DHW Tank)
Relay 3
10A
ZONE2 Pump
Relay 4
10A
ZONE3 Pump
(System)
Flame Rod
Relay 1
Relay 2
Relay 3
Relay 4
MCU 2
Relay 5
Relay 6
Relay 7
Relay 8
Relay 9
Relay 10
Relay 11
Front Panel
Relay 7
Output
Relay 8
Output
Appendixes 125