COLOR CODING
V : Violet
W : White
O : Orange
R : Red
BK : Black
BL : Blue
GY : Gray
G : Green
BR : Brown
Y : Yellow
WIRING DIAGRAM
HOT
NEUTRAL
10A(FUSE)
RELAY 1
CIRCULATION PUMP
RELAY 2
FREEZE PREVENTION
HEATER
ARRESTER
VARISTOR
VARISTOR
DC140V
DC140V
POWER
CONTROLLER
FAN CONTROL
OUTPUT
E
FAN COMBUTION FAN
DC12V
FAN ROTATION
SPEED INPUT
EARTH
C
SECONDARY
A
B
FAN CURRENT
VALUE INPUT
15V POWER CIRCUIT
RELAY 1
RELAY
DRIVING
CIRCUIT
RELAY 2
Sub-CPU
SUB
CONTROL
UNIT
CPU
DU
GND
CENTRAL
PROCESSING
UNIT
GAS PROPORTION VALVE
POWER CONTROL CIRCUIT
IG DRIVING CIRCUIT
FR FLAME ROD
WATER LEVEL ELECTRODE
DETECTION CIRCUIT
D
WATER OUTLET
THERMISTOR
WATER INLET
THERMISTOR
FLAME DETECTING CIRCUIT
IGNITER
E
BYPASS FLOW CONTROL VALVE
<E(N,P)19 Model Only>
SOLENOID
SV0 VALVE 0
SOLENOID
SV1 VALVE Q1
B
C
HEAT EXCHANGER FLOW CONTROL VALVE
DC15V
HIGH LIMIT
SWITCH
A
WATER FLOW SENSOR
PRIMARY
IG
FAN
PULSE
CONTROL
CIRCUIT
EARTH
HEAT EXCHANGER
THERMISTOR
D
AIR INLET
THERMISTOR
GAS SOLENOID VALVE
DRIVING CIRCUIT
EXHAUST
THERMISTOR
SOLENOID
SV2 VALVE Q2
SOLENOID
SV3 VALVE Q3
<E(N,P)19 Model Only>
SOLENOID
SV4 VALVE Q4
5V POWER CIRCUIT
GND
THERMAL FUSE
HEAT
EXCHANGER
FLOW CONTROL
VALVE
(VDC)
(VCC)
(Fully open)
(GND)
BK
V
W
G
O
R
Y
BL
BK
V
W
G
O
R
Y
BL
WR
<E(N,P)19 Model Only>
(VDC)
BYPASS
FLOW CONTROL
VALVE
(VCC)
(Fully open)
(GND)
BK
V
W
G
O
R
Y
BL
CIRCULATION PUMP
(OPTIONAL)
BK
V
W
G
O
R
Y
BL
R
W
W
<CN186>
<CN42>
HEAT EXCHANGER
THERMISTOR
W
BK
W
BK
WATER OUTLET
THERMISTOR
AIR INLET
THERMISTOR
WATER INLET
THERMISTOR
EXHAUST
THERMISTOR
MAIN
CIRCUIT
BOARD
W
W
O
R
BL
G
W
Y
<CN78>
R
V
O
W
BK
G
BK
BL
V
G
O
W
<E(N,P)18 Model Only>
<CN197>
Manifold Gas Pressure
Increase Button
Manifold Gas Pressure
Decrease Button
Minimum Manifold
Pressure Set Button
Maximum Manifold
Pressure Set Button
W
(GND)
<CN186>
RorV
BL
REMOTE CONTROLLER
BL
WW
BL
Y
R
Y
Y
R
R
WATER LEVEL
ELECTRODE
BK
<CN89>
BL
W
R
BK
W
G
BL
BL
WW
BL
BK
W
RorG
BL
BL
W
R
BK
W
G
BL
BL
BL
<DIP SWITCH>
BL
BL
MAIN CIRCUIT
BOARD
FLAME ROD
<CN101>
BL
Other Unit in Quick Connect
Multi System
(For Quick Connect Multi System Only)
Quick Connect Cord 2(Optional)
R
BK
W
G
BL
BL
R
BK
W
G
BL
BL
BL
WW
WW
WW
WW WW
WW
WW
WW
WW
WW
WW
WW WW
WW
WW
WW
<CN38>
GY
BL
O
BK
BL
R BL W
BR
HIGH-LIMIT
SWITCH
THERMAL FUSE
G
W
W
R
BK
W
W
RorBL
RorBL
(Pulse)
(Vcc)
(GND)
G
Y
R
BL
BLorG
GROUND
<CN27>
BR
Y
BL
R
W
<CN104>
W
BKorBL
Y
R
BL
O
BK
GROUND
HEAT EXCHANGER
FLOW SENSOR
<CN102>
W
Y
W
W
W
W
W
W
WW
WW
WW
WW
WW
WW
WW
WW
W
W
W
W
WW
WW
WW
WW
WW
WW
WW
WW
FAN MOTOR
BR
Y
BL
R
BR(Vdc)
Y(FG)
BL(GND)
R(Vcc)
BR
Y
BL
R
BK
BK
W
<CN103>
POWER
CIRCUIT
BOARD
W
<CN92>
FREEZE PREVENTION HEATER
BK(W)
G
W(BK)
GROUND
LIGHTNING
PROTECTION
<AC120V>
BK(W)
W(BK)
GROUND
G