2685
7
GB
4.3 ELECTRODE SETTING
4.4 COMBUSTION HEAD SETTING
(See fig. 12 and 13)
This is done when fitting the nozzle, with the blast tube
removed. It depends on the output of the burner and is
carried out by rotating the regulating rod, till the terminal
plane of the blast tube is level with the set-point, as indi-
cated in the schedule.
In the sketch on fig. 12, the combustion head is set for an
output of 3.25 GPH at 12 bar, while the shutter is level with
set-point 3, as required by the above schedule.
Combustion head settings indicated in the schedule are
valid for most cases.
The setting of the fan output according to the installation
should normally be done only through the air damper.
Should one subsequently want to retouch also the setting of
the combustion head, with the burner running, operate on
the rod (1) with a 6 mm spanner (2), (see fig. 13).
TURN TO THE RIGHT: (sign +)
In order to increase the volume of air entering the combus-
tion chamber and thus diminishing its pressure.
There is a reduction of CO
2
and the adhesion of the flame
to the air diffuser disc improves.
(Setting advisable for ignitions at low temperatures).
TURN TO THE LEFT: (sign –)
In order to reduce the volume of air entering the combustion
chamber and thus increasing its pressure. The CO
2
improves and the adhesion of the flame to the diffuser tends
to reduce.
(This setting is not advisable for ignitions at low
temperatures).
In any case do not bring the combustion
head setting more than one point away from that indicated
in the schedule. One set-point corresponds to 3 turns of the
rod; a hole (3) at its end facilitates counting the number of
turns.
4.5 AIR DAMPER ADJUSTMENT,
(see fig. 14, page 8)
The mobile air damper (1) operated by the jack (2) assures the complete opening of the air intake. The regula-
tion of the air-rate is made by adjusting the fixed air damper (3), after loosing the screws (4). When the optimal
regulation is reached, screw tight the screws (4) to assure a free movement of the mobile air damper (1).
Before removing or assembling the
nozzle, loosen the screw (B, fig. 11)
and move the electrodes ahead.
ATTENTION
Fig. 11
4 ±
0.3 mm
D5961
B
MOVE THE ELECTRODE
HOLDER BACKWARDS
TO THE END
6.5
±
0.5 mm
Fig. 12
1
2
3
6
D5967
Fig. 13
Blast tube
Shutter
Terminal plane of the blast tube
D5398
2
1
3
5
Regulating rod
