11
2916089
GB
Installation
4.6
Choice of nozzles for 1st and 2nd stage
The burner complies with the emission requirements of the EN
267 standard.
In order to guarantee that emissions do not vary, recommended
and/or alternative nozzles specified by Riello in the Instruction
and warning booklet should be used.
Both nozzles must be chosen from among those listed in table
(Tab. B).
The first nozzle
determines the delivery of the burner in the 1st
stage.
The second nozzle
works together with the 1st nozzle to deter-
mine the delivery of the burner in the 2nd stage.
The deliveries of the 1st and 2nd stages must be contained within
the value range indicated on pag. 5.
Use nozzles with a 60° spray angle at the recommended pres-
sure of 12 bar.
The two nozzles usually have equal deliveries, but the 1st stage
nozzle may have the following specifications if required:
a delivery less than 50% of the total delivery whenever the
back-pressure peak must be reduced at the moment of fir-
ing: the burner allows good combustion values also with a
ratio 40 - 100% between the 1st and 2nd stage;
a delivery higher than 50% of the total delivery whenever
the combustion during the 1st stage must be improved.
Tab. B
(1)
light oil: density 0.84 kg/dm
3
- viscosity 4.2 cSt/20 °C - tem-
perature 10 °C
Example
with the TECNO 70-L model
:
Boiler output = 635 kW - efficiency 90 %
Output required by the burner =
635 : 0.9
= 705 kW;
705 : 2
= 352 kW per nozzle;
therefore, two equal, 60°, 12 bar nozzles are required:
1° = 7.0 GPH - 2° = 7.0 GPH,
or the following two different nozzles:
1° = 6.0 GPH - 2° = 8.0 GPH,
or:
1° = 8.0 GPH - 2° = 6.0 GPH.
WARNING
It is advisable to replace nozzles every year dur-
ing regular maintenance operations.
WARNING
The use of nozzles other than those specified by
Riello S.p.A. and inadequate regular maintenance
may result into emission limits non-conforming to
the values set forth by the regulations in force, and
in extremely serious cases, into potential hazards
to people and objects.
The manufacturing company shall not be liable for
any such damage arising from nonobservance of
the requirements contained in this manual.
GPH
kg/h (1)
kW
12 bar
10 bar
12 bar
14 bar
5.00
5.50
6.00
6.50
7.00
7.50
8.00
8.30
8.50
9.00
9.50
10.0
10.5
11.0
12.0
12.3
13.0
13.8
14.0
15.0
15.3
16.0
17.0
17.5
18.0
19.0
19.5
20.0
21.5
22.0
19.2
21.1
23.1
25.0
26.9
28.8
30.8
31.9
32.7
34.6
36.5
38.4
40.4
42.3
46.1
47.3
50.0
53.1
53.8
57.7
58.8
61.5
65.4
67.3
69.2
73.0
75
76.9
82.7
84.6
21.2
23.3
25.5
27.6
29.7
31.8
33.9
35.2
36.1
38.2
40.3
42.4
44.6
46.7
50.9
52.2
55.1
58.5
59.4
63.6
64.9
67.9
72.1
74.2
76.4
80.6
82.7
84.8
91.2
93.3
23.1
25.4
27.7
30.0
32.3
34.6
36.9
38.3
39.2
41.5
43.8
46.1
48.4
50.7
55.3
56.7
59.9
63.3
64.5
69.2
70.5
73.8
78.4
80.7
83.0
87.6
89.9
92.2
99.1
101.4
251.4
276.3
302.4
327.3
352.3
377.2
402.1
417.5
428.2
453.1
478.0
502.9
529.0
553.9
603.7
619.1
653.5
693.8
704.5
754.3
769.7
805.3
855.1
880.0
906.1
956.0
980.9
1005.8
1081.7
1106.6
