18
IGNITION AND REGULATION WITH FUEL OIL
1) Make sure that the nozzle’s characteristics (delivery and spray angle) are suitable for the furnace
(see BT 93531). Otherwise, replace it with another suitable nozzle.
2) Make sure there is fuel in the tank and that, at least visually, it is suitable for the burner.
3) Make sure there is water in the boiler and that the system’s gate valves are open.
4) Make absolutely sure that the flue products can be discharged freely (boiler and flue dampers open).
5) Make sure the voltage of the electrical supply to which the machine is to be connected matches that required
for the burner, and that the electrical connections of the motors and heating elements are correctly arranged
for the available voltage. Also make sure that all electrical connections made on the site, are correctly executed
according to our wiring diagram.
6) Make sure that the combustion head enters the firebox as far as that required by the boiler manufacturer.
Make sure the combustion head is in the right position for delivering the fuel required (the gap between the
disc and head must be considerably closed where a relatively small amount of fuel is supplied; whenever the
nozzle must supply a rather large amount of fuel, the gap between the disc and head must be relatively open)
- see the chapter “Combustion head adjustment”.
7) Remove the cover on the air regulation servomotor that controls the combustion air damper. Following the
specific instructions (see BT 8653/1) move the air regulation cam of the first flame to the position required for
supplying sufficient air to the flame. Likewise, adjust the position of the air regulation cam for the second
flame. Then, adjust the solenoid valve insertion cam (second flame connection) to an intermediate position
between those for the cams referred to above.
8) If already connected, disconnect the thermostat or pressure switch for the second flame to avoid it being
connected.
9) Make sure the settings on the two thermostats (minimum and adjustment) are suitable for the type of fuel to be
used. Knowing the nominal viscosity value of the fuel to be used, the viscosity/temperature diagram can be used
to determine the exact pre-heating temperature for the fuel oil. Remember that the fuel must reach the nozzle at
a viscosity of about 2° E. To avoid interference that could cause the burner to stop, the regulation thermostat
must be set at a temperature of 15 - 20° C higher than that of the minimum thermostat. Once the burner has
been ignited, check the reading on the pre-heater thermometer to ensure that the thermostats are working
properly. Set the thermostat that controls the heating elements built into the line filter (if fitted) to about 50° C.
10) Start the auxiliary fuel supply circuit, make sure it is working properly, and adjust the pressure to about 1 bar.
11) Remove the cap on the vacuum meter union and then slightly open the gate valve on the fueldelivery pipe.
Wait until the fuel flows from the hole without bubbles, then close the gate valve.
12) Fit a pressure gauge (full scale about 3 bar) to the seat provided on the pump at the union for the vacuum
meter to check the pressure at which the fuel reaches the burner pump. Fit a pressure gauge (full scale about
30 bar) to the seat provided on the pump, to check the pressure at which the pump is working.
Fit a pressure gauge (full scale 30 bar) to the relative union on the return pressure regulator for the first flame
(see BT 8713/1) to check the return pressure of the first and second flames.
13) Then, open the gate valves and any other valves on the fuel piping.
14) Turn the switch on the control panel to the “0” (open) position to prevent the heating elements and vacuum
tank from being connected, and switch on the power to the electrical line connected to the burner. Press the
relative switches to make sure the two motors (fan and pump) turn in the correct direction. If necessary invert
the two wires of the main line to change the direction of rotation.
15) Start the burner pump, by pressing the “fill tank” pushbutton until the pressure gauge indicating the pump
working pressure, shows a slight pressure. Low pressure in the circuit means that the pre-heating tank has
been filled.
16) Use the switch on the control panel to deliver power to the unit. When the command is received from the
relative thermostat, the heating elements that heat the fuel in the tank are switched on, as well as the heater
for the line filter, if fitted. When the heating elements are switched on, a LED on the control panel comes on.
