Dunkirk Excelsior EXB Series User Manual
Page 57
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20.1 Combustion
A. Nozzles- See “17 - Oil Burner, Nozzle, & Air Settings”
on page 46.
B. Fuel leaks - Any fuel leak between pump and nozzle
is detrimental to good combustion results. Look for
wet surfaces in air tube, under ignitor, and around air
inlet. Repair any such leaks as they may cause erratic
burning of fuel and in extreme case may become fire
hazard.
C. Dirt - Fuel filter is required to prevent clogging nozzle
or nozzle strainer and produce poor spray pattern
from nozzle.
D. Water - Water in fuel in large amounts will stall fuel
pump. Water in fuel in smaller amounts will cause
excessive wear on pump. Water doesn’t burn, it chills
the flame and causes smoke and unburned fuel to
pass out of the combustion chamber and clog flue
ways of the boiler.
E. Cold Oil - If oil temperature approaching fuel pump is
40°F or cooler, poor combustion or delayed ignition
may result. Outside fuel tank above grade or fuel lines
in shallow bury may be the cause.
F. High Altitude Installation - Air openings must be
increased at higher altitudes. Use combustion analyzer
and set to 11.5% for initial setting.
G. Start up noise - Late ignition is cause of start up
noises. If it occurs recheck for electrode settings,
flame shape, air or water in fuel lines.
H. Shut-down noise - Post Purge timed 15 seconds
should eliminate shut-down noise.
20.2 Oil Primary Control
I. Burner (control) will not come on.
I. No power to control.
II. Control is in soft lockout or restricted mode. Press
reset button for more than 1 second to exit soft
lockout. If control has recycled three times within
same call for heat, it will enter into restricted mode.
To reset from restricted mode, refer to Page 41
for
more details.
III. CAD Cell seeing light.
IV. CAD cell is defective.
J. Burner (control) will light, then shut down after short
time, then restart after one (1) minute.
I. CAD cell is defective.
II. Air leaking into oil line causing flame out.
III. Defective nozzle causing flame to be erratic.
IV. Excessive airflow or draft causing flame to leave
burner head.
V. Excessive back pressure causing erratic flame.
K. Control locks out after trial for Ignition. (TFI)
I. No oil to burner.
II. Shortened electrodes
III. Clogged nozzles.
IV. Airflow too high.
V. Ignitor module defective.
VI. CAD cell defective.
VII. Oil valve stuck open or closed.
To isolate fuel problems: disconnect fuel system and fire
out of auxiliary container of clean, fresh, warm #2 fuel
oil from another source. If burner runs successfully when
drawing out of container problem is in fuel or fuel lines.
If flame is not established within 15 seconds of oil valve
actuation (known as Trial For Ignition or TFI) soft lockout
will occur. Soft lockout is indicated by flashing red LED
located on oil primary control.
20 - TROUBLESHOOTING
NOTICE
Restricted lockout without retries will occur if flame
is lost three times during one call for heat. this is
indicated by a steady on red LED.