Part number 550-100-090/0809
gas
-
fired
water
boiler
—
Boiler Manual
96
Annual startup
(continued)
Figure 107
Burner assembly
Check burner flame
The boiler contains ceramic fiber materials.
Use care when handling these materials per
instructions on page 93 of this manual. Fail-
ure to comply could result in severe personal
injury.
Inspect flame through observation window using the
1.
procedure on page 36.
If flame is unsatisfactory at either high fire or low fire,
2.
turn off boiler and allow boiler to cool down. Then
remove burner and clean it thoroughly using a vacuum
cleaner or compressed air. Do not use compressed air to
clean burner if performed inside a building.
To access the burner, remove the heat exchanger cover
3.
plate following the procedure beginning on page 109.
When replacing burner, ensure gasket is in good condi-
4.
tion and correctly positioned. After tightening the three
retainer screws, bend up the retainer tabs as shown in
Figure 107 to prevent screw rotation.
Reattach the cover plate using the method given in
5.
Figure 113, page 110 or Figure 115, page 111.
After servicing, reinstall boiler components. Retest
6.
boiler.
Check flame signal
Navigate to Diagnostics/Inputs on the U-Control display (see
1.
Figure 102, page 86). The flame signal value must be at least 20
above the Shutdown values given in Figure 106.
Flame signal shutdown values
Figure 106
Model
Ultra –
Shutdown
flame signal
Model
Ultra –
Shutdown
flame signal
80
95
230
100
80 HA
95
230 HA
100
105
135
299
130
105 HA
135
299 HA
130
155
80
399
120
155 HA
80
399 HA
120
NOTE: “HA” means high altitude, 5500 feet or more above seal level.
If the flame signal drops to less than 20 above the Shutdown
2.
values, the U-Control will attempt to correct by increasing the
boiler firing rate to increase flame signal.
A lower flame signal may indicate a fouled ignitor or damaged ig-
3.
nitor insulation. If cleaning the ignitor does not improve, ground
wiring is in good condition, and ground continuity is satisfactory,
replace the ignitor.