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Wiring Connections
56
T3.15A/250V
Thermostat
HEATER
Power
M-Valve
MAIN
Flow2
AD5
Flame
GND
GND
5V
RPM
PWM
GND
24V
AD4
G
B
5V
A
24V
FAN
GND
5V
B-
B+
A+
5V
G
5
RX 5V
TX
GND
FLOW1
AD1
AD2
W-V
CO
PUMP
AC110V/60HZ
A-
AD3
GND
Fire
G
OUT
GND
CN15
CN13
CN14
CN8
F1
CN10
CN1
CN4
CN12
CN11
24V
B-
B+
A+
5V
A-
OUT
GND
Main control board
Bypass
water
flow
Ignitor Flame sensor
Flue
temperature
sensor
CN18
A
B
C
B
D
①
Area A
T3.15A/250V
Thermostat
HEATER
M-Valve
MAIN
FAN
PUMP
Power
AC110V/60HZ
CN15
F1
CN1
CN12
RPM PWM GND
24V
CN4
FAN control
T3.15A/250V
HEATER
Power
M-Valve
MAIN
FAN
PUMP
AC110V/
60HZ
CN15
F1
CN1
CN12
L N
Ground
Fan
Gas
valve
Thermostat
RPM PWM GND
24V
CN4
FAN control
Thermostat