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8. Pilot Test
Once the burner has been set for the firing rates
intended, the pilot must be checked for proper operation
and safety. The minimum pilot test is done to insure that
a pilot which can be seen by the scanner will light the
main flame.
a. During a startup sequence, measure the time
required to light the main flame after the fuel valves
have been energized. This will be used to monitor
the test with reduced pilot.
b. Lock the flame safeguard into the pilot position
(refer to the manual for the flame safeguard for this
setting)
c. Adjust the gas pressure regulator to the pilot for a
minimum value while still holding the minimum
signal strength for the scanner.
d. Release the flame safeguard from the pilot
position and allow it to cycle though the main flame
proving sequence.
e. This reduced pilot must reliably light the main flame.
Monitor the time from the main fuel valve opening
and do not allow the burner to continue if the time is
more than an additional two to three seconds from
the initial time measured above.
f. Run through two or three cycles.
g. Failures due to reduced scanner signal are also
acceptable.
THE MINIMUM PILOT TEST REQUIRES CLOSE SUPERVISION
OF THE COMBUSTION PROCESS. FAILURE TO CLOSELY
MONITOR THE MAIN FLAME TEST TIME COULD RESULT IN
DAMAGE, INJURY OR DEATH.
h. If the pilot does not light the main flame under
these test conditions, adjust the fuel pressure to the
primary (pilot) zone
i. The infrared detector must be tested for hot
refractory pickup. This test is performed to make
sure that the scanner does not see hot refractory
that could be mistaken for a flame.
SC Manual
WARNING
j. After the burner has been operating for some time
at high input levels and the refractory in the vessel
is hot, the burner should be cycled off while
monitoring the scanner signal.
k. The flame signal should drop off quickly as the
flame goes out and should be well below the
minimum level (indicating a flame) at the end of the
post purge cycle.
l. The UV detector must be tested for spark pick-up.
Turn the burner on, with the pilot shut off, during the
ignition cycle the flame signal should be well below
the minimum level (indicating a flame).
m. If the flame signal does not drop out as required,
this may indicate a faulty scanner or amplifier.
9. Burner Shutdown
Normal operation of the burner will allow the operating
controls to shut the burner down when the load demand
is satisfied. If the burner needs to be shut down for any
reason, the "ON-OFF" switch can be used to quickly turn
the burner off. This will instantly cause the fuel valves
to close and start a post purge cycle to remove any
unburned fuel from the vessel.
In an emergency shutdown, all fuel and electrical power
should be de-energized or turned off to secure the burn-
er. This would include the main power disconnect, the
manual gas shutoff valve at the drop down line and if
equipped, the manual oil valve to the nozzle.
It is recommended that the burner be manually driven to
low fire before turning the burner off, as this reduces the
dynamic and thermal stress. If the burner will remain off
for some time, the manual fuel valves, fuel pumps and
power supply should be turned off.
ALWAYS KEEP THE FUEL SUPPLY VALVE SHUT OFF WHEN THE
BURNER IS SHUT DOWN FOR AN EXTENDED PERIOD OF TIME.
10. Restarting After Extended Shutdown
Extended shutdowns require the same startup process
as those outlined above. In addition, the following
advanced cleaning must be done:
a. The air atomized oil nozzle should be removed and
cleaned, if pressure atomized they should be
replaced. Use care in cleaning to preserve the
sharp edges of the nozzle, which are required to
maintain good atomization.
b. The oil filter and strainer must be removed and
cleaned prior to starting.
DO NOT START THE BURNER UNLESS ALL CLEANOUT DOORS
ARE SECURED IN PLACE.
Page 24
CAUTION
CAUTION
Startup and Operating Adjustments
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