Air Regulation On The Combustion Head - Regulation Of The Distance Between The Disk And The Nozzle - baltur BT 15 N Manual De Instrucciones

The following should then occur:
- the fuel is intercepted and consequently the flame is extinguished.
- The pre-ventilation pre-washing phase is repeated.
c) Keep the photoresistant cell in the dark and the burner will start up again but, as the photoresistant cell
doesnot see the light, the burner will go to shut down within the time pre-set by the programmer.
The control box can only be unblocked by pressing manually the appropriate pushbutton.
3) To check the thermostat efficiency, run the burner until the water in the tank reaches a temperature of at least
50 °C. Then turn the thermostat control knob, to lower the water temperature, until an opening click is heard
which causes the burner to stop. The thermostat should trip within a maximum tolerance of 5 to 10 °C in respect
to the control thermometer (boiler thermometer); if not, change the setting on the thermostat scale to match that
of the thermometer.
AIR REGULATION ON THE COMBUSTION HEAD
The combustion head is equipped with a regulating device which close (by moving forwards) and opens (by moving
backwards) the air passage between the disk and the head. By closing the passage, it is possible to achieve high
pressure upstream the disk and therefore high velocity and turbulence for the low outputs as well.
High velocity and air turbulence ensure a better penetration in the fuel and are therefore an optimum mixture; they
allow the burner to operate with a lower grade of smoke and good flame stability.
It might be necessary to have high air pressure upstream the disk in order to avoid flame pulsations and it is considered
practically indispensable when the burner is operating with a pressurized furnace and/or high thermal load.
It is evident from the above, that the device which closes the air on the combustion head should be put in such a
position as to always obtain a decidedly high air pressure value behind the disk.
It is advisable to regulate in such a way as to achieve a closing of the air on the head; this will necessitate a considerable
opening of the air shutter which regulates the flow to the burner's fan suction. Obviously, these adjustments should be
carried out when the burner is operating at maximum delivery desired. In practice, start regulating by putting the
device which closes the air on the combustion head in an intermediate position, start up the burner and make trial
adjustments as previously described. When maximum delivery desired has been reached, proceed with correcting
the position of the device which closes the air on the combustion head; move it backwards or forwards in such a way
as to obtain an air flow suitable to the delivery, with the air regulation shutter in suction considerably open.
When reducing the air passage on the combustion head, avoid closing it completely.
Proceed with perfect centering with respect to the disk. It must be pointed out thet, if perfect centering with respect to
the disk is not obtained, bad combustion and excessive heating of the head could occur which would result in its rapid
deterioration. A control can be carried out by looking through the spy hole situated at the back of the burner; then
tighten home the screws that lock the position of the air regulation device on the combustion head.
Note: Check that ignition occurs regularly, because when the device has been moved forwards, it could occur that the
air velocity in exit is so high as to render ignition difficult.
If this does happen, move it backwards, gradually, until it reaches the correct position and ignition occurs regularly.
This position should be definitive.
REGULATION OF THE DISTANCE BETWEEN THE DISK AND THE NOZZLE
The burners are provided with a device which permits a variation in the distance between the disk and the nozzle.
The distance between the disk and the nozzle has already been set by the manufacturer and should only be reduced
if the atomized fuel cone in exit from the nozzle wets the disk and fouls it up.
(see BT 8608/1)
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