Part number 550-100-180/0917
90
Annual startup
(continued)
Inspect ignition electrode
1. Remove the ignition electrode from the boiler heat ex-
changer burner end section. See image at right. Ignition
electrode is longer than the fl ame sensor (see below) and
has a brown ceramic insulator.
2. Remove any white oxides accumulated on the ignition
electrode using steel wool. If the ignition electrode cannot
be cleaned satisfactorily, replace ignitor with a new one.
3. Reinstall ignition electrode, making sure gasket is in good
condition and correctly positioned.
4. Replace gasket if necessary.
5. Make sure the ignition electrode ground wire is under the top
screw that secures the ignitor to the casting.
Th
e ignition electrode must be installed on the burner
end section. Th
e fl ame sensor must be installed on the
piping end section. Installing these components in
the wrong locations could cause poor ignitions and
lockout, resulting in loss of heat.
Check ignition wiring
1. Check ignition cable electrical resistance. A good cable will have
resistance between 900 and 1000 ohms. Replace if not acceptable.
2. Inspect boiler ground wire from ignition electrode to ground
terminal strip.
3. Verify all wiring is in good condition and securely att ached.
4. Check ground continuity of wiring using continuity meter.
5. Replace ground wires if results are not satisfactory.
Inspect fl ame sense assembly
1. Remove the fl ame sensor assembly from the boiler heat
exchanger piping end section. See image at right. Flame
sensor insertion length is shorter than the ignition
electrode (see above) and has a pink ceramic insulator.
2. Remove any white oxides accumulated on the fl ame sense
rods using steel wool. If the fl ame sense rods cannot be
cleaned satisfactorily, replace fl ame sense assembly with
a new one.
3. Reinstall fl ame sense assembly, making sure gasket is in good
condition and correctly positioned.
4. Replace gasket if necessary.
5. Inspect the fl ame sense harness and connections. Replace if neces-
sary. See WARNING above about fl ame sensor location.
Check all boiler wiring
1. Inspect all boiler wiring, making sure wires are in good condition
and securely att ached.
Check control settings
1. Use the display to navigate through all sett ings. Adjust sett ings
if necessary.
2. Check
sett ings of external limit controls (if any) and adjust if
necessary.
&IGURE
Gas valve and venturi
Gas valve M5 bolts
Air inlet hose bolts
Air fl ow switch hose
Plastic reference tube
&IGURE
Burner access
Nuts
Observation
window
Mixing adapter
NOTE: Ignitor ground wire must be attached
to the ignitor mounting screw.
&IGURE
Burner removal and replacement
Burner
Gasket
IMPORTANT — Align the burner fl ange and
gasket notches with the pins in the casting.
SlimFit
®
Series 2
COMMERCIAL
CONDENSING
GAS
-
FIRED
WATER
BOILER
—
Boiler Manual
