INSTALLATION AND OPERATION INSTRUCTIONS
6-10
SL 80-399 MODULATING GAS BOILER
SL 26-260 G3, SL 40-399 G3 MODULATING GAS BOILERS
Diagram 6.2-2: Internal wiring diagram
Better
Boilers
24 Vac
120 Vac
black
white
orange
white
17
16
green
red
red
yellow
white
white
blue
blue
white
blue
green
blue
TB1
10
9
Flue Gas
Temperature
Sensor
4 x plug
100-025A
4 x plug
Mains
Power Supply
5 x plug
3 x plug
Electrode
and Flame
Sensing Rod
Assembly
Spark
black
black
yellow
red
white
black
blue
VS Out 0-10VDC
brown
SL 40-399 G3 and SL 26-260 G3
Gas
Valve
Combustion
Fan
Replacement internal wiring
must meet or exceed the
ratings of the wiring supplied
from the factory.
green
Transformer
green
green
white
white
black
Upper Vessel
High Limit
Switch
white
yellow
white
red
white
white
yellow
white
black
brown
black
blue
orange
orange
blue
red
blue
Inlet Water
Pressure
Sensor
green
white
black
white
black
yellow
To Boiler Pump
green
green
Grounded
to case
Inlet Water
Temperature
Sensor
Outlet Water
Temperature
Sensor
2 x plug
red
3
4
10
9
15
2
1
1
1
2
5
6
3
4
22
13
27
28
6
4
5
120Vac
LWCO Probe
INTERNAL WIRING DIAGRAM
NG150
IBC Control Board
P 501
P 102
P 101
P3
6
P 702
5
white
IBC SIM Ignition Module
3
4
2
1
P2
7
8
5
9
10
2
3
4
5
6
7
8
9
11
T1b
brown
orange
white
orange
red
white
black
black
orange
Exhaust
Pressure
Switch