•
The modification must be performed by the qualified gas installer only, according
to the technical data, by replacement of the nozzle in the main burner and
adjustment of the nozzle in the ignition burner.
Replacement of the nozzle in the main burner (fig. 10)
Table 3: Characteristics of nozzles and burners
Rated
Gas
Pressure
power
type
28-30/37
G30
11.5 kW
-31
G20
13 kW
G25
Low flame
power
3.00 kW
Fig. 10
Main
burner
(mbar)
nozzle
Ø (mm)
1.80
50/50
1.60
20
3.05
20
3.30
25
3.15
Gas consumption
G30
0.907 kg/h
G31
0.893 kg/h
G20
1.376 m
G20
1.376 m
G25
1.600 m
a) Remove the burner ring (1) .
b) Unscrew the fixing bolt (2) which holds the
burner and is accessible from below.
c) Dismantle a complete air mixing chamber (3)
by turning it counterclockwise.
d) Release the main burner nozzle from the nozzle
bracket (4) and replace it with the nozzle
designed for the relevant type of gas (data
related to the nozzle are shown in the table 3
"Characteristics of burners and nozzles").
e) Install the removed parts in the reverse order.
Ignition
Primary
burner
chamber
nozzle
H (mm)
Ø (mm)
0.20
0.20
adjustable
adjustable
adjustable
3
/h
3
/h
3
/h
Secondary
air
air
chamber
12
opened
12
opened
5
closed
5
closed
5
closed
Nozzle
bypass
Ø 0.95
Ø 0.85
adjustable
adjustable
adjustable
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