16
IGNITER
SHIELD
SCREW
WASHER
MALE CONNECTOR
FEMALE CONNECTOR
SCREW
BRACKET
BURNER
SENSOR
1.
To help maintain proper flame sense, the sensor
should be removed from its mounting bracket and its
metal rod cleaned using steel wool or emery cloth.
Rub briskly to remove build up of dust, dirt and
aluminum oxide. Be careful not to fracture the
ceramic base of the sensor. See Fig. 12 for sensor
location.
2.
Check the flame sensor’s ceramic base for any
cracks. If cracks are found, replace the sensor.
FIG. 12
■
For proper flame sense operation, the flame sensor tip
must be properly positioned within the burner flame.
Normally 12.7 mm to 19 mm is sufficient. See Fig. 13.
FIG. 13
FLAME SENSOR
Complete this procedure at least once during the heating season.
BURNER
FLAME
BURNER
CASTING
FLAME SENSOR
3/8 TO 1/2 IN.
12.7 mm TO 19 mm
IGNITER
1.
Open the burner end access panel.
2.
Disconnect the plastic male and female plugs located
at the end of the igniter leads. See Fig. 12
3.
Remove the screw securing the igniter shield and the
igniter to the mounting bracket. Remove the igniter
and shield.
4.
Connect the male plug on the replacement igniter to
the female connector plug on the red wires which
lead back to 9 pin connector housing.
5.
Position the igniter so the lip on back side of igniter is
resting on the edge of the mounting bracket and so
the mounting hole in the igniter aligns with the
mounting hole in the bracket.
6.
Slide the igniter shield over the igniter so hole in
shield aligns with hole in igniter and bracket.
7.
Install igniter retaining screw and tighten snugly. DO
NOT OVERTIGHTEN. Overtightening can cause cracks
in base of igniter, possibly leading to future igniter
failure.
■
Handle the igniter only by its ceramic base, or by its
leads.
■
Center the igniter shield over the igniter element,
making sure the shield does not touch the igniter
element, otherwise igniter damage will occur when the
igniter is energized..
■
D o n ot ove r t i g h te n t h e i g n i te r m o u n t i n g s c r ew.
Overtightening will crack the base of the igniter, leading
to premature failure.
Summary of Contents for AW250
Page 2: ......
Page 26: ...25 Electrical Connection and Ladder Diagram...