19
2916089
GB
Burner calibration
7.1
Firing
Notes on safety for the first start-up
Set switch 1) (Fig. 22) to "ON".
During the first firing, during the passage from the 1st to the 2nd
stage, there is a momentary lowering of the fuel pressure caused
by the filling of the 2nd stage nozzle tubing. This lowering of the
fuel pressure can cause the burner to lock-out and can some-
times give rise to pulsations.
Once the following adjustments have been made, the firing of the
burner must generate a noise similar to the noise generated dur-
ing operation. If one or more pulsations or a delay in firing in re-
spect to the opening of the light oil solenoid valve occur, see the
suggestions provided on pag. 25: causes 34 ÷ 42
7.2
Operation
The optimum calibration of the burner requires an analysis of the
flue gases at the boiler outlet and interventions on the following
points:
1st and 2nd stage nozzles
See the information listed on pag. 11.
Combustion head
The adjustment of the combustion head already carried out need
not be altered unless the 2nd stage delivery of the burner is
changed.
Pump pressure
12
bar: this is the pressure calibrated in the factory which is usu-
ally sufficient for most purposes. Sometimes, this pressure must
be adjusted to:
10 bar:
in order to reduce fuel delivery. This adjustment is possi-
ble only if the surrounding temperature remains above 0°C. Nev-
er calibrate to pressures below 10 bar, at which pressures the
cylinders may have difficulty in opening;
14 bar:
order to increase fuel delivery or to ensure firings even at
temperatures of less than 0°C.
In order to adjust pump pressure, use the relevant screw 5)
(Fig. 21 pag. 18)
1st stage fan air gate valve
Keep the burner operating at 1st stage by setting the switch 2)
(Fig. 22) to the 1st stage position. Opening of the air gate valve
6) (Fig. 24) must be adjusted in proportion to the selected nozzle:
the index 1) (Fig. 23) must be aligned with the notch 2) (Fig. 23)
specified in table (Tab. E) This adjustment is achieved by turning
the hex element 2) (Fig. 24):
– in rh direction (- sign) the opening is reduced;
– in lh direction (+ sign) the opening increases.
Example:
TECNO 70-L
- 1st stage nozzle 6.0 GPH:
2.3 notch (Fig. 23) aligned with index 1).
When the adjustment is terminated lock the hex element 2)
(Fig. 24) with the ring nut 1).
Tab. E
2st stage fan air gate valve
Set switch 2)(Fig. 22 pag. 19) to the 2nd stage position and ad-
just the air gate valve 6)(Fig. 24) by turning the hex element
4)(Fig. 24), after having loosened the ring nut 3) (Fig. 24).
Air pressure at connection 1)(Fig. 25) must be approximately the
same as the pressure specified in the table (Fig. 25) plus the
combustion chamber pressure measured at connection 2). Refer
to the example in the adjacent figure.
7
Burner calibration
WARNING
The first start-up of the burner must be carried out
by qualified personnel, as indicated in this manual
and in compliance with the standards and regula-
tions of the laws in force.
Burner
Fig. 22
1
2
D469
Off
On
Stage
1st
2nd
WARNING
Check the correct working of the adjustment, com-
mand and safety devices.
D699
Fig. 23
Fig. 24
TECNO 70-L
TECNO 100-L
TECNO 130-L
GPH
N°
GPH
N°
GPH
N°
5
6
7
8
9
2.0
2.3
2.6
2.7
2.8
7
8
9
10
11
12
13
14
2.0
2.1
2.2
2.4
2.6
2.7
2.8
2.9
10
11
12
13
14
15
16
17
18
19
2.0
2.1
2.2
2.3
2.5
2.6
2.7
2.8
2.9
3.0
