11
20013756
GB
3)
Select the manual
(MAN)
mode operation, and switch
ON
the burner.
4)
When the burner is alight, press the
(+)
button to manually drive the servomotor to the high fire position
and check that the gas pressure also increases.
5)
Check the gas flow rate at high fire. To set the correct flow rate use the screw adjustments
V
and
N
on
the valve body (mainly
V
). Increasing the setting of either
V
or
N
increases the gas flow.
6)
Adjust the manual air damper to give the required CO
2
level in the flue products. If adjusting the air damp-
er alters the gas flow rate then adjust
V
accordingly.
7)
Decrease the servomotor position to low fire by pushing the
(–)
button. Check the gas flow rate and adjust
if necessary, with screw
N
only, to give the required CO
2
level in the flue products.
8)
If the low fire output is then more or less than required, adjust
CAM III (Orange)
accordingly.
Any adjustment of screw
N
will affect the high fire gas rate.
9)
Return the servomotor to the high fire position. Re-adjust the high fire gas rate using only screw
V
.
10)
Again return the servomotor to the low fire position and re-adjust the low fire gas rate using only screw
N
.
11)
Repeat steps (9) and (10) two or three times until no re-adjustment of screws
V
and
N
is necessary.
12)
Finally return the selector switch to the automatic
(AUT)
mode position.
5.4 COMBUSTION ADJUSTMENT
In conformity with Efficiency Directive 92/42/EEC the application of the burner on the boiler, adjustment and
testing must be carried out observing the instruction manual of the boiler, including verification of the CO
and CO
2
concentration in the flue gases, their temperatures and the average temperature of the water in
the boiler.
It is advisable to set the burner according to the type of gas used and following the indications of the table:
IONIZATION CURRENT
The minimum current necessary for the con-
trol box operation is 2 µA. The burner nor-
mally supplies a higher current value, so that
no check is needed.
Anyway, if you want to measure the ionization
current, you have to open the connector
(CN3)
(see electrical scheme page 7) fitted on the
wire and insert a microammeter.
EN 676
AIR EXCESS:
max. output
1.2
– min. output
1.3
GAS
Theoretical max. CO
2
0 % O
2
Setting
CO
2
%
CO
mg/kWh
NO
x
mg/kWh
= 1.2
= 1.3
G 20
11.7
9.7
9.0
100
170
G 30
14.0
11.6
10.7
100
230
G 31
13.7
11.4
10.5
100
230
Probe
Connector
Control box
terminal strip
D5006
1
