A.O. Smith 100 Series Service Handbook page 28

CONNECTORS PINS
1
2
3
J7 4
5
6
7
1
2
3
4
5
6
7
J8
8
9
10
11
12
1
2
3
4
J9
5
6
7
1
2
3
4
J10
5
6
7
8
FS +
Flame +
FS -
Flame -
28
TERMINOLOGY
SIPHON
F1
Not Used
SYS_ENABLE
LGP
HGP
Not Used
SOLA1_PWR
SOLA1_S_RTN
Not Used
INLET TEMP
INLET TEMP Common
Not Used
Not Used
OUTLET TEMP
OUTLET TEMP Common
OUTLET TEMP
HEADER +
HEADER -
Not Used
Not Used
Not Used
STACK TEMP
STACK Common
STACK TEMP/Heat Exchanger
Unit)
Not Used
REMOTE RESET
TOD (Time of Day)
TOD/REMOTE RESET COMMON
MODULATION 4 - 20mA (+) (Out)
MODULATION 0 - 10 VDC (+) (Out) 0 to 10 VDC Voltage modulation signal out, 10 mA max.
MODULATION COMMON (-)
Not Used
Not Used
SPECIAL CONNECTIONS
Testpoint for Flame signal. 0 to 10
VDC
Testpoint for Flame signal - Ground
reference.
Servicing should only be performed by a Qualified Service Agent
DESCRIPTION AND RATING
Condensation Switch Input.
Flapper Switch Input.
Annunciator for System Enable Switch.
Annunciator for Low Gas Pressure Switch.
Annunciator for High Gas Pressure Switch.
24VAC Power Input form Terminal Block.
24VAC Return Input from Terminal Block.
Supply for, and signal input from 10K or 12K Ohm NTC Inlet
Temperature sensor. Connects to Pin 2 on Inlet Temperature
Sensor.
Ground reference for the Inlet Temperature Sensor. Connects
to Pin 1 on Inlet Temperature Sensor.
Supply for, and signal input from 10K or 12K Ohm NTC Outlet
Temperature Sensor. Connects to Pin 2 on Outlet Temperature
Sensor.
Ground reference for the Outlet Temperature Sensor. Connects
to Pins 3 & 4 on Outlet Temperature Sensor.
Supply for, and signal input from 10K Ohm NTC Outlet
Temperature Sensor. Connects to Pin 1 on Outlet Temperature
Sensor.
Supply for, and signal input from 10K or 12K Ohm NTC
Header Sensor.
Ground reference for the Header Sensor.
Supply for, and signal input from 10K or 12K Ohm NTC Flue
Sensor. Connects to Pin 2 on Flue Sensor.
Ground reference for the Flue Sensor. Connects to Pin 3 & 4
on Flue Sensor.
Supply for, and signal input from 10K Ohm NTC Flue Sensor.
Connects to Pin 1 on Flue Sensor.
Open/Ground Input that has functionality corresponding to
pushing/releasing the local reset.
Open/Ground Input which switches operating set points.
Ground reference for time of day and remote reset inputs.
4 to 20 mA Current modulation signal out into a 600 Ohm.
Ground reference for voltage and current modulation signals.