Ignition And Regulation With Fuel Oil - baltur BT 75 DSPN Manual De Instrucciones

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IGNITION AND REGULATION WITH FUEL OIL

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1) Check that the nozzle characteristics (output and spray
angle) are suitable for the furnace (see BT 9353/1).
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If not, replace the nozzle with one of the right type.
2) Check there is fuel in the tank and that it is suitable (at least
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judging by its appearance) for the burner.
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3) Check there is water in the boiler and that the equipment gates
are open.
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4) Make absolutely sure that combustion waste can be freely
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discharged (boiler gate and flue open).
5) Check that the voltage of the connecting power supply line
corresponds to burner voltage. Also check that electric
connections on motors and elements are correctly installed
according to the voltage available. Check that all electric
connections carried out on the premises have been done
correctly according to our wiring diagram.
6) Make sure that the blast-tube penetrates into the fur-
nace to the depth called for by the boiler manufacturer.
Check that air regulation device on the blast-tube is in the
position considered suitable for the desired fuel supply (the
air passage between disk and blast-tube must be well closed
for low volume fuel supply. Vice-versa, if the nozzle has a
high output, the passage should be relatively open). See the
chapter "Blast-tube regulation".
7) Remove the protective cover on the rotating disk, fitted to the
modulation motor. The adjusting screws for controlling fuel
and combustion air are fitted here.
8) Set the two modulation switches to the "MIN" (minimum) and
"MAN" (manual) positions.
9) Check that the setting of the two pre-heater thermostats (one for
minimum level, the other for regulation) is suitable for the type
of fuel you wish to use. Once you know the nominal viscosity
value for the fuel you wish to use, you can find the exact fuel oil
pre-heating temperature on the viscosity-temperature diagram.
Bear in mind that fuel must reach the nozzle at a viscosity not
exceeding 2° E. To avoid interference which would stop the
burner operating, the regulation thermostat should be set to a
temperature 15÷20° C higher than the minimum level thermo-
stat. After igniting the burner, check that thermostats operate
correctly, by reading the thermometer on the pre-heater. Set
to about 50° C the thermostat that controls the resistance
built into the line filter.
10) Put the auxiliary fuel circuit into operation, checking its effi-
ciency and setting pressure to about 1 bar.
11) Remove the cap from the pump vacuum gauge take-off point.
Then slightly open the gate on the fuel inflow tube. Wait till
fuel flows out of the hole without any air bubbles and close
the gate.
12) Fit a pressure-gauge (with scale minimum of about 3 bar) to the
pump vacuum-gauge take-off point and check the pressure
of the fuel flowing into the burner pump. Fit a pressure-gauge
(with scale minimum of about 30 bar) to the pressure-gauge
take-off on the pump, and check its working pressure. Fit a
pressure-gauge (with scale minimum of about 30 bar) to the
return pressure take-off to check the value determining output
(see BT 8712/3).
13) Now open all the gates and any stop-cocks etc., on the fuel
pipes.
14) Set the switch on the control panel to "O" position (open) to
avoid cutting-in the elements on an empty tank, and cut-in
power to the electric line to which the burner is connected.
Check that the two motors (fan and pump) turn in the right
direction (do this by pushing the relevant remote switches
manually). If necessary, change over two of the main power
line wires in order to reverse rotation direction.
15) Put the burner pump into operation. Do this by pressing the
relative remote switch until the pump working-pressure mete-
red by the relative pressure gauge indicates slight pressure. If
there is low pressure in the circuit, this means that pre-heater
tank has been filled.
16) Switch on the control panel switch to cut-in power to the
equipment. This in turn switches on (via a command from
the relative thermostat) the elements heating fuel in the tank
and the line filter. At the same time, heating elements for the
atomizer unit and pump are cut-in (this only applies to models
....D). Cutting-in of elements is indicated by the pilot-lamp on
the control panel.
17) The minimum-level thermostat closes when fuel in the pre-
heater reaches the temperature to which the thermostat is
set. When the minimum level thermostat closes this does
not immediately cut-in the burner command/control equip-
ment. This equipment is cut-in by the regulation thermostat
(by commutation contact) when it switches off the elements
because fuel temperature has reached the level set on the
regulation thermostat. Burner start-up therefore begins only
when the elements are switched off and maximum pre-heater
temperature has been reached (provided that the boiler and
safety thermostats or pressure switches are cut-in). When
the burner is in operation, an auxiliary relay (connected to
the minimum level thermostat) prevents it stopping when the
regulation thermostat switches on the contact to cut-in the
elements again (see wiring diagram). When the command/
control equipment is cut-in, the burner ignition phases begin.
The programme entails a combustion chamber preventilation
phase coupled to precirculation of hot oil at low pressure
over the entire fuel circuit in the burner. Burner ignition is as
described in the preceding chapter "Fuel oil operation". The
burner ignites at minimum level.
18) When the burner operates at minimum level, air should be
set to the quantity needed to ensure good combustion. Screw
down or unscrew the adjusting screws near the point of contact
with the lever that transmits movement to the combustion air
regulation gate. Air quantity for minimum level should prefera-
bly be slight, so that perfect ignition may be guaranteed even
in the most difficult cases.
19) After setting minimum level air, position the modulation
switches to "MAN" and "MAX".
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