Page 11
WARNING
Shock hazard.
Disconnect power before servicing. Control is
not field repairable. If control is inoperable, sim-
ply replace entire control.
Can cause injury or death. Unsafe operation will
result if repair is attempted.
4. SureLight Ignition Control (A92) Figure 5
Control 69M08
The Lennox SureLight ignition system consists of ignition
control board, ignitor and sensor. The board and ignitor
work in combination to ensure furnace ignition and ignitor
durability. The SureLight integrated board controls all ma-
jor furnace operations. The board also features two LED
lights (DS1 red and DS2 green) for troubleshooting and
two 120 volt accessory terminals, each rated at (1) one
amp. The board also features a 3 amp fuse for low voltage
overcurrent protection. Table 4 gives control terminal des-
ignations. Tables 5 and 6 show jack plug terminal designa-
tions. See table 11 for troubleshooting diagnostic codes.
Units equipped with the SureLight board can be used with
either electronic or electro−mechanical thermostats with-
out modification. The SureLight ignitor is made of durable
silicon−nitride. Ignitor longevity is also enhanced by volt-
age ramping by the control board. The board finds the low-
est ignitor temperature which will successfully light the
burner, thus increasing the life of the ignitor.
TABLE 4
SURELIGHT BOARD TERMINAL DESIGNATIONS
COOL
Blower − Cooling Speed (120V)
HEAT
Blower − Heating Speed (120V)
PARK
Unused Blower Lead (not energized)
FAN
Continuous Low Blower Speed
EAC
Accessory Terminal (120V)
XFMR
Transformer (120V)
LINE
Input (120V)
HUM
Heat Only Accessory (120V)
5 Terminals
120V Neutral
FS
Flamer Sensor
SURELIGHT INTEGRATED CONTROL BOARD
FIGURE 5
3 AMP, 32
VAC FUSE
TABLE 5
SURELIGHT BOARD 4 PIN DESIGNATIONS
PIN #
FUNCTION
1
Combustion Air Inducer Line
2
Ignitor Line
3
Combustion Air Inducer Neutral
4
Ignitor Neutral
TABLE 6
SURELIGHT BOARD 12 PIN DESIGNATIONS
PIN #
FUNCTION
1
Prove Switch and Limit Out
2
Not Used
3
24V Hot
4
Not Used
5
Rollout Switch In 1
6
24V Common
7
Limit In
8
Ground
9
Gas Valve Common
10
Prove Switch In
11
Rollout Switch Out 2
12
Gas Valve Hot
