38
111079-01 - 12/20
FR
Installation & Service Manual
A. COMBUSTION
1. NOZZLES — Although the nozzle is a relatively
inexpensive device, its function is critical to
the successful operation of the oil burner.
The selection of the nozzle supplied with the
FR boiler is the result of extensive testing
to obtain the best flame shape and efficient
combustion. Other brands of the same spray
angle and spray pattern may be used but may
not perform at the expected level of CO
2
and
smoke. Nozzles are delicate and should be
protected from dirt and abuse. Nozzles are
mass-produced and can vary from sample to
sample. For all of those reasons a spare nozzle
is a desirable item for a serviceman to have.
2. FUEL LEAKS — Any fuel leak between the
pump and the nozzle will be detrimental to
good combustion results. Look for wet surfaces
in the air tube, under the ignitor, and around
the air inlet. Any such leaks should be repaired
as they may cause erratic burning of the fuel
and in the extreme case may become a fire
hazard.
3. SUCTION LINE LEAKS — Any such leaks
should be repaired, as they may cause erratic
burning of the fuel and in extreme cases may
become a fire hazard. Whatever it takes, The
Oil Must Be Free of Air. This can be a tough
problem, but it must be resolved. Try bleeding
the pump through a clear tube. There must
be no froth visible. There are various test
kits available to enable you to look at the oil
through clear tubing adapted to the supply line
at the pump fitting. Air eliminators are on the
market that have potential. Also, electronic
sight glasses are being used with good
success. At times, new tubing must be run to
the tank or new fittings put on. Just make sure
you get the air out before you leave.
Any air leaks in the fuel line will cause an
unstable flame and may cause delayed ignition
noises. Use only flare fittings in the fuel lines.
4. GASKET LEAKS — If 11.5 to 12.5% CO
2
with a #1 smoke cannot be obtained in the
breeching, look for air leaks around the
burner mounting gasket, observation door,
and canopy gasket. Such air leaks will cause
a lower CO
2
reading in the breeching. The
smaller the firing rate the greater effect an air
leak can have on CO
2
readings.
5. DIRT — A fuel filter is a good investment.
Accidental accumulation of dirt in the fuel
system can clog the nozzle or nozzle strainer
and produce a poor spray pattern from the
nozzle. The smaller the firing rate, the smaller
the slots become in the nozzle and the more
prone to plugging it becomes with the same
amount of dirt.
6. WATER — Water in the fuel in large amounts
will stall the fuel pump. Water in the fuel in
smaller amounts will cause excessive wear on
the pump, but more importantly water doesn’t
burn. It chills the flame and causes smoke and
unburned fuel to pass out of the combustion
chamber and clog the flueways of the boiler.
7. COLD OIL — If the oil temperature
approaching the fuel pump is 40°F or lower,
poor combustion or delayed ignition may
result. Cold oil is harder to atomize at the
nozzle. Thus, the spray droplets get larger and
the flame shape gets longer. An outside fuel
tank that is above grade or has fuel lines in a
shallow bury is a good candidate for cold oil.
The best solution is to locate the tank near the
boiler in the basement utility room or bury the
tank and lines deep enough to keep the oil
above 40°F. Check environmental issues with
local authorities having jurisdiction.
8. FLAME SHAPE — Looking into the
combustion chamber through the observation
port, the flame should appear straight with no
sparklers rolling up toward the crown of the
chamber. If the flame drags to the right or left,
sends sparklers upward or makes wet spots on
the target wall, the nozzle should be replaced.
If the condition persists look for fuel leaks, air
leaks, water or dirt in the fuel as described
above.
9. HIGH ALTITUDE INSTALLATIONS —
Air openings must be increased at higher
altitudes. Use instruments and set for 11.5 to
12.5% CO
2
.
10. START-UP NOISE — Late ignition is the
cause of start-up noises. If it occurs recheck for
electrode settings, flame shape, air or water in
the fuel lines.
11. SHUT DOWN NOISE — If the flame runs out
of air before it runs out of fuel, an after burn
with noise may occur. That may be the result
of a faulty cut-off valve in the fuel pump, or it
may be air trapped in the nozzle line. It may
take several firing cycles for that air to be fully
vented through the nozzle. Water in the fuel or
poor flame shape can also cause shut down
noises.
12
Troubleshooting