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124 Appendixes
12.2 Wiring Diagram
Cascade Line(RS-485)
CNB1
CNG1
CNF1
CNK1
Water Pressure Sensor
Main Gas Valve1
Main Gas Valve2
Burner
Flame Rod
Ignitor
CNA1
CNI1
Ground
CNR1
Dual Venturi
CNO1
ON
OFF
Boiler Pump FUSE
(250VAC_10A)
ZONE3 Pump FUSE
(250VAC_10A)
ZONE2 Pump FUSE
(250VAC_10A)
ZONE1 Pump FUSE
(250VAC_10A)
DHW Priority
Air Handler
Boiler Pump
CND1
CNP1
CNP2
CNA1
CON1
AC_N
ZONE1 Pump (DHW TANK)
ZONE2 Pump
ZONE3 Pump
(SYSTEM)
Power Trans
AC_L
IN
OUT
AC_N
AC_L
IN
OUT
AC_N
AC_L
IN
OUT
Ground
Ground
Ground
NFB-H
(24V 75VA)
Ground
W
ARNING
ELE
CTRI
CAL SHOCK H
A
ZARD
*T/S: Thermostat **Temp: Temperature ***Factory jumper is connected as default. Remove it when using an additional appliance.
N
O
TICE
Ground
Main Switch
(AC)
External Input (AC 120V)
AC_L
CNX1
External Pump
Ground
AC_L
IN
OUT
Front Panel
Fan
N
L
CON2
CON1
Fuse
(125V 20A)
Fuse
(250V 3.15A)
IN
OUT
AC24V
T/S INPUT
*T/S_3
ZONE3
ZONE2
ZONE1
DHW
AC24V
T/S INPUT
*T/S_2
AC24V
T/S INPUT
*T/S_1
AC24V
T/S INPUT
*T/S_4(DHW)
CNT1
CNT2
CNT3
CNT4
SUPPLY
RETURN
OUTDOOR
DHW TANK
System Supply **Temp Sensor
System Return **Temp Sensor
Outdoor **Temp Sensor
DHW Tank **Temp Sensor
AC_N
r o s n e S p
m
e T * * y l p p u S
t i m i L p
m
e T h g i H
) r e n r u B (
r o s n e S p
m
e T * * n r u t e R
r o s n e S p
m
e T * * 1 t s u a h x E
r o s n e S p
m
e T * * 2 t s u a h x E
r o s n e S e r u s s e r P r i A
t i m i L p
m
e T h g i H
CNJ1
CND1
Vent Installation Detector
CNV3
CNV2
CNV1
CNC3
ZONE3
LWCO
ZONE2
ZONE1
***LWCO
LW
CO
AC24V
AC24V
AC24V
AC24V
CNC4
CNC5
CNC6
CNC1
Zone Valve1
Zone Valve2
Zone Valve3
CNC2
Pumps must be ele
ct
rically
gr
ounded as
requi
red
by N
ational Ele
ct
rical
Cod
e.
For your safety, turn off electrical power supply before making any electrical connections to avoid possible electric hazard. Failure to do so can cause severe personal injury or death.
Summary of Contents for NFB-175H
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