3328
12
GB
4.5
BURNER ADJUSTMENT
To achieve optimal burner adjustment, the flue gases produced by combustion must be analysed as they leave
the generator. In conformity with Efficiency Directive 92/42/EEC, the burner must be applied to the generator,
adjusted and tested in compliance with the instruction manual of the generator in question, including checking of
CO and CO
2
concentration in flue gases and their temperature.
Check in this order:
- maximum output;
- minimum output;
- firing output.
The
maximum output
must correspond with the the output required by the boiler used. To increase or decrease
its value, adjust trimmer MAX on the control box (Fig. 5).
Measure the gas delivery on the contactor to precisely establish the burnt output.
Using a smoke analyser measure the value of the CO
2
or the O
2
in order to optimise the burner calibration.
The correct values are: CO
2
8,5 -9% or O
2
5-5.5%.
To correct these values act on the gas valve in the following way:
- To increase the gas delivery and the CO
2
: turn the screw V1 in anticlockwise direction (unscrew)
- To reduce the gas delivery and the CO
2
: turn the screw V1 in a clockwise direction (screw up)
The
minimum output
must correspond with the the output required by the boiler used. To increase or decrease
its value, adjust trimmer MIN on the control box (Fig. 5).
Measure the gas delivery on the contactor to precisely establish the burnt output.
Using a smoke analyser, measure the value of the CO2 or the O
2
in order to optimise the burner calibration.
The correct values are: CO
2
8.5-9% or O
2
5-5.5%.
To correct these values act on thee gas valve in the following way:
- To increase the gas delivery and the CO
2
: turn the screw V2 in a clockwise direction (screw up)
- To reduce the gas delivery and the CO
2
: in an anticlockwise direction (unscrew)
Firing output
must come to approx. 70-80% of the maximum output.
To increase or decrease its value, adjust trimmer START on the control box (Fig. 5)
4.6
COMBUSTION HEAD
The combustion head comprises a highly heat re-
sistant cylinder whose surface features numerous
holes, encased in a metal "mesh". The air-gas
mixture is pushed inside the cylinder and out of
the head through the holes in the perimeter.
Combustion starts when the air-gas mixture is
ignited by a spark generated by the electrode.
The metal "mesh" is the combustion head's most
essential element since it improves burner perfor-
mance considerably.
The flame developed on the surface of the head is perfectly retained and adheres to the mesh when operating at
the maximum setting. This allows modulating ratios as high as 6:1, avoiding the danger of flashback when modu-
lating is at its minimum. The flame features an extremely compact geometry, meaning that there is no risk of con-
tact between the flame and parts of the boiler, consequently eliminating the possible problem of poor combustion.
The flame's structure means that smaller combustion chambers can be developed, designed to exploit this parti-
cular feature.
D9714
