Cleaver-Brooks CBH 40 - Oil Burner; Burner Nozzles

Chapter 5-Adjustment and Maintenance
after in accordance with a planned maintenance
program.
The operating limit control may be checked by
allowing steam pressure or water temperature to
increase until the burner shuts down. Depending
upon the load, it may be necessary to manually in-
crease the firing rate to raise steam pressure to the
burner shut off point. If load is heavy, the header
valve can be closed or throttled until the pressure
increases. Observe the steam gauge to check the
cutoff pressure as the operating limit control shuts
the burner down. Open the header valve to release
steam pressure or vent steam and check the cut-in
setting as the burner restarts. Check the high-low
fire control for desired operating pressure range.
Water temperature, on a hot water boiler that may
be operating at less than full load, may be raised
by manually increasing the firing rate until the
burner shuts down thru the action of the operating
limit control. Observe the thermometer to verify
the desired settings at the point of cut-out and
again when burner restarts. Check the modulating
control for the desired temperature range.
Observe the ignition and programming control
operations to make sure that they are correct.
Check the proper operation and setting of the low
water cut-off (and pump operating control, if used).
Proper operation of the flame failure device should
be checked at time of starting and at least once a
week thereafter. Refer to previous section for in-
formation on flame safety checks.
Check for tight shut-off of all fuel valves. Despite
precautions and strainers, foreign material may
lodge under a valve seat preventing tight closure.
Promptly correct any conditions causing leakage.
F. Oil BURNER
GENERAL
There are relatively few adjustments that can be
High Fire Nozzle
Low
Fire (CBH 25-50A)
CBH
Nozzle
Intermediate Nozzle
Boiler
(CBH 50-100)
Size
Size
Spray
Part
Size
Spray
Part
Angle
Number
Angle
Number
25 2.5 30° HV
899-93
2.0
30°
HV 899-23
30 3.0 30° HV
899-26
2.5
30° HV
899-93
40 4.5
30° HV
899-31
3.0
30°
HV
899-26
50 A
8.3
30° HV
899-60
3.0
30°
HV 899-26
50 4.0
45°
PLP
899-12 4.0
45°
PLP 899-12
60
5.0
45° PLP
899-18 5.0
45°
PLP
899-18
70
6.0 45°
PLP 899-35
6.0
45°
PLP
899-35
80
7.0 45°
PLP 899-61 7.0
45°
PLP
899-61
100 8.3 45°
PLP 899-39
8.3
45° PLP
899-39
made to the burner drawer, however, a check
should be made to see that all components are
properly located and that all holding devices such
as setscrews properly tightened. Figures 5-3 and 5-
4
cover typical burner drawers and show pertinent
dimensions.
The burner drawer should be periodically in-
spected for evidence of damage due to improperly
adjusted combustion. The air cooling tubes
surrounding the nozzles should be inspected oc-
casionally for any carbon residue or any clogging
that might be caused by unusual dusty or lint-
laden atmosphere. The setting of the oil nozzle in
relation to the opening in the cooling tube IS Im-
portant and should be maintained.
DIFFUSER
Proper positioning of the diffuser should be main-
tained so that oil spray or flame does not impinge
on it. Remove any carbon or other deposits if any
have accumulated so that air flow pattern is not
affected. Do not attempt to change the gap or angle
of the fins.
BURNER NOZZLES
Efficient oil burner operation requires clean noz-
zles.
The nozzles deliver a spray of extreme fine-
ness to assure proper mixing with the air stream. If
at any time the flame becomes "stringy or lazy" it
is possible that one or more of the nozzles is
clogged
or worn. Even though the oil pressure
gauge may indicate correct pressure, plugged or
partially plugged nozzles will greatly reduce oil
delivery.
The nozzles may be cleaned. However, if they ap-
pear worn or if they have been in service for a con-
siderable time, it is more economical to replace
them. Any cleaning should be done with a wood
splinter rather than with any metal to avoid
damaging the hole in the tip or the oil grooves.
Check strainer and clean if necessary.
High Fire
Nozzle
Max. Max.
Input Firing Rate
BTU/Hr.
GPH
Size
Spray Part
Angle Number
2.0 30°
HV
899-23 1,045,000
7.5
2.5
30° HV 899-93 1,255,000
9.0
3.0 30° HV 899-26 1,675,000
12.0
4.0
30° HV 899-20
2,095,000 15.0
4.0
45°
PLP 899-12
2,095,000 15.0
5.0
45°
PLP 899-18
2,510,000 18.0
6.0
45° PLP
899-35
2,930,000
21.0
7.0
45° PLP
899-61
3,350,000 24.0
8.3
45°
PLP 899-39
4,185,000
30.0
NOTE: Nozzle size is rating at 100 PSI oil pressure. Flow rate increases with pressure.
FIGURE 5-2. NOZZLE SIZES, LOCATION AND FIRING RATE
5-8