Normal Operation - CleaverBrooks FLX Operation, Service And Parts Manual

Profire V Burner
perature.
5. After the boiler has reached operating temperature or
pressure, turn the potentiometer switch in small incre-
ments to the high-fire position. This will cause the
metering valve to close, resulting in an increase in the
oil pressure feeding the burner nozzle. In high-fire the
oil metering valve should be in the fully closed position
and the fuel oil pressure should be about 300 psi. Check
high-fire at this point using combustion instruments.
High-fire combustion analysis typically is 3.5% to 4%
O2. Verify maximum input rate by measuring the oil
meter if available or by weighing the oil.
6. The burner should be set up and maintained to yield
smoke spot levels less than a #1 spot (ASTM D2156
Shell-Bacharach Scale) to minimize soot buildup in the
boiler.
7. do not disturb established low-fire adjustment. Allow
the burner to return to low-fire position before adjusting
high or intermediate settings.
When conditions covered above are assured, refer to F and G
of this section.
COMBINATION GAS-OIL BURNERS
In general, the combination fueled system is to be started first
using oil, because, as a fuel, oil has a greater combustion air
requirement than natural gas.
Refer to the Gas Burner or Oil Burner adjustment procedures
and to Section 4 - ADJUSTMENTS.
Once the adjustments are set for oil, shut down the burner and
restart the adjust the natural gas fuel. DO NOT READJUST
THE AIR DAMPERS. The adjustment is made by balancing
the fuel input rate against the existing flow of combustion air.
When conditions covered above are assured, refer to F and G
of this section.
Notice:
SIZE 1 & 2 COMBINATION GAS/OIL
UNITS USE A DIRECT COUPLING FROM THE
BLOWER MOTOR TO THE OIL PUMP. WHEN FIR-
ING GAS FOR AN EXTENDED PERIOD OF TIME,
THE COUPLING SHOULD BE MANUALLLY
REMOVED AND REPLACED ONLY WHEN FIRING
OIL. IF THE COUPLING IS LEFT CONNECTED TO
THE BLOWER MOTOR, ENSURE THAT THERE IS
PROPER OIL CIRCULATION AT ALL TIMES TO
AVOID DAMAGE AND SEIZURE OF THE PUMP.

NORMAL OPERATION

Normal operation must be with the MANUAL-AUTO switch
selector on AUTO.
750-177
In automatic operation, the operating cycle always proceeds
sequentially through pre-purge, pilot ignition, main flame
ignition, run and post-purge. The length of purge and ignition
trial vary according to the type of programmer used.
During the run cycle, burner input is regulated to the load
demand by the modulating pressure or temperature control on
the boiler. The burner will continue to modulate until the
operating pressure or temperature is reached.
Programmer control operation should be tested when the
burner is initially placed into service, when a control is
replaced, and at scheduled intervals in the maintenance
program.
Refer to adjustments procedures and maintenance
instructions given in Sections 4 and 5.
SHUTDOWN
When the operating limit control setting is reached or the
burner switch is turned OFF, the following sequence occurs:
The fuel valve(s) de-energize and flame extinguishes. The
blower motor continues running during post-purge (if so
equipped with post-purge feature).
At the end of the post-purge the blower motor is de-energized.
The programmer returns to its starting position and stops.
Unit is ready to restart.
Abnormal shutdown might result from motor overload flame
outage, low water, current or fuel supply interruption,
combustion or atomizing air pressure below minimum level,
tripped circuit breakers, blown fuses, or other interlock
devices. Check for cause and correct before restarting burner.
Safety shutdown caused by ignition or flame failure will
actuate a red indicator light and energize an audible alarm (if
so equipped). If the programmer has a non-recycling
interlock circuit, any interruption in this circuit during the
pre-purge or firing cycle will cause a safety shutdown. This
type of shutdown requires manual reset of the programming
control and must be corrected before operation can be
resumed.
Chapter 2
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