20146119
32
GB
Start-up, calibration and operation of the burner
6.1
Notes on safety for the first start-up
6.2
Adjustments prior to ignition
Check the adjustment of the head as shown in pag. 15.
Check the adjustment of the air damper as shown in
pag. 16.
Slowly open the manual valves situated upstream from the
gas train.
Adjust the air pressure switch (Fig. 23) to the start of the
scale.
Purge the air from the gas line.
We recommend using a plastic tube routed outside the build-
ing and to purge air until gas is smelt.
6.3
Combustion adjustment
In conformity with EN 676 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 CO2 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 in Tab. N.
Tab. N
6.4
Air pressure switch
Adjust the air pressure switch (Fig. 23) after performing all other
burner adjustments with the air pressure switch set to the start of
the scale. With the burner function at the required output, turn the
knob slowly in a clockwise direction until burner lockout.
Then turn the knob anticlockwise to an extent that is around 20%
of the adjusted value and then check that the burner starts up
properly.
If the burner locks out again turn the knob slightly in an anticlock-
wise direction.
6
Start-up, calibration and operation of the burner
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.
WARNING
Check the correct working of the adjustment, com-
mand and safety devices.
WARNING
Refer to paragraph “Safety test - with gas ball
valve closed” on page 33 before the first start-
up.
CAUTION
Before starting up the burner, it is good practice to
adjust the gas train so that ignition takes place in
conditions of maximum safety, i.e. with gas deliv-
ery at the minimum.
EN 676
Air excess: max. output.
1.2 – min. output
1.3
GAS
Theoretical max
CO2
0 % O2
Setting CO2 %
CO
mg/kWh
NOx
mg/kWh
= 1.2
= 1.3
G 20
11.7
9.7
9.0
100
170
G 25
11.5
9.5
8.8
100
170
G 30
14.0
11.6
10.7
100
230
G 31
13.7
11.4
10.5
100
230
WARNING
In conformity with the standard, the air pressure
switch must prevent the air pressure falling below
80% of the adjusted value and the CO in the flue
gases exceeding 1% (10,000 ppm).
To check this, insert a combustion analyser in the
flue, slowly reduce the burner air setting (for ex-
ample with a piece of cardboard) and verify that
the burner locks out before the CO value in the
flue gases exceeds 1%.
Fig. 23
D7404
