151B0801 R5 3/28/2006
9
BEFORE OPERATING THE FURNACE
CHECK BURNER ALIGNMENT WITH
COMBUSTION CHAMBER. THE END
CONE OF THE AIR TUBE MUST BE
CENTRED TO THE ACCOMODATING
RING PROVIDED IN THE DESIGN OF
THE COMBUSTION CHAMBER.
ADJUST ALIGNMENT AS
NECESSARY BEFORE THE FIRST
FIRING.
OIL BURNER NOZZLES
O4HD-091A
furnaces are certified for
multiple firing rates, ranging from
approximately 58,000 to 79,000 BTU/hr.
The
O4HD-140A
furnaces are certified
for multiple firing rates of approximately
87,000 115,000 BTU/hr. By changing the
oil burner nozzle within the specific
Model Range, and temperature rise, the
furnace may be fired at an ideal rate for
a wide range of structures.
BURNER ELECTRODES
Correct positioning of the electrode tips
with respect to each other, to the fuel oil
nozzle, and to the rest of the burners is
essential for smooth light ups and proper
operation. The electrode tips should be
adjusted to a gap of 5/32”, 1/16” ahead
of the nozzle, 5/16” above the centerline
of the nozzle. The “Z” dimension (front
edge of the burner head to the front face
of the nozzle is 1-1/8 inches.
Electrode positioning should be checked
before the first firing of the furnace.
The electrode porcelains should be free
of cracks, the electrode tips should be
tapered and free of burrs, and the
contact rods must be clean and be in
firm contact with the ignition transformer
contact springs. The electrodes must not
come into contact with the burner head.
OIL BURNER SET-UP
The burner air supply is adjusted to
maintain the
fuel to air
ratio
to obtain
ideal combustion conditions. A lack of air
causes "soft" and "sooty" flames,
resulting in soot build-up throughout the
heat exchanger passages. Excess
combustion air causes a bright roaring
fire and high stack temperatures
resulting in poor fuel efficiency.
PREPARATIONS:
Drill a ¼” test port in the venting, ideally
at least 2 flue pipe diameters away from
the furnace breeching, if venting
horizontally from the furnace, or from the
flue pipe elbow if venting vertically before
reaching the furnace. (See Figures 4 and
5).
The test port will allow flue gas samples
to be taken and stack temperatures to be
measured.
Before starting the burner, check the
burner alignment with the combustion
chamber (fire pot), check that the correct
nozzle is tightened into place, and that
the burner electrodes are properly
positioned.
The Beckett burner bulk air band is
should be closed, and the air shutter
initial setting should be approximately
7.00.
Note A
: Locate hole at least 6 inches on
the furnace side of the draft control.
Note B
: Ideally, hole should be at least
12 inches from breeching or elbow.
PROCEDURE:
Start the burner and allow it to run at
least ten minutes. Set the air shutter to
give a good flame visually. Manipulating
the air shutter on the left side of the
burner controls the combustion air
supply to the burner, and, if necessary,
the bulk air band. To adjust, loosen the
bolt on the movable shutter. Move the
shutter gradually until a good flame
(visually) has been achieved. Re-snug
the bolt.
Check the initial draft setting as the
furnace warms up. The draft may be
measured at the test port. The breech
draft should be approximately - 0.05”
w.c. to obtain an over fire draft reading of
- 0.02 inches w.c.
Check the oil pump pressure. Standard
operating pressure is 100 PSIG.
After reaching steady state, take a
smoke test. If not indicating a trace, set
the combustion air controls to provide a
trace.
Typically, the CO
2
reading will range
from 11.5% to 13.5%.
After the air adjustments have been
completed, and the air shutter or air
adjustment plate has been secured, re-
check the over fire draft and take another
smoke test to ensure that the values
have not changed.
Fig.4 Vertical Smoke test Location
Fig.3 Horizontal Smoke test Location
