baltur SPARKGAS 30 LX, Instruction

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0006080799_200708
a) The gas pipes have not been sufficiently air-bled, and thus the gas quantity is not sufficient to allow a
stable flame.
b) The “lock” with presence of flame may be caused by instability of the same in the ionisation zone for
an incorrect air/gas ratio. Remedy is by varying the quantity of supplied air and/or gas so as to find
the correct ratio. The same problem may be caused by a wrong air/gas distribution in the combustion
head. Remedy is by operating on the combustion head regulation device, by adjusting the closing or
opening of the air passage between head and gas diffuser.
11) Set the burner to minimum flame (modulation servomotor set to minimum), check the quantity and appearance
of the flame making the necessary adjustments: see instructions elating to the gas valve model MB-VEF...
Afterwards, check the supplied gas quantity by reading the meter. If necessary, adjust the gas output and
the relevant combustion air by operating as described above. Then, check the combustion with the special
instruments (see chapter “Combustion control”.
2) After adjusting the “minimum”, set the modulation switches to MAN (manual) and MAX (maximum) po-
sition. The air regulation servomotor sets to “maximum” and as a consequence, also the gas supply
reaches the “maximum”. The quantity of supplied gas is then checked by reading the meter.
With burner ignited at the maximum existing output, measure the gas flow rate by calculating the difference
between two reads performed after one minute from one another. By multiplying the measured value by sixty,
a sixty-minute flow rate – that is, one hour – is obtained. By multiplying the hourly output (m
/h) by the gas
heat value, you obtain the delivered power in Kcal/h, which must correspond or be very close to that required
by the burner (lower heat value for methane = 8550 Kcal/h).
Avoid operating the burner if the flow rate is
more than the admissible for the boiler so as to prevent possible damages to the same. Shut down
the burner after the two meter reads.
13) To change the maximum gas output, operate on the air flow rate regulator since the gas flow rate automati
-
cally adjust to the air supply. Then, operate on the cam regulating the air damper maximum aperture position
(see dr. n° 0002933220). Reduce the aperture angle of the air damper to reduce the gas flow rate, and vice
versa. To change the gas/air ratio, see instruction of gas valve MB-VEF...
4) Afterwards, check the combustion with the special instruments and if necessary, check the existing regulation
(air and optionally gas). Check with the special instruments that the carbon oxide (CO) percentage in
the flue gas does not exceed the maximum admissible value of 0.1% and that CO
2
does not exceed
10% for methane. (See chapter “Combustion control”)
15) After adjusting the operation to the high flame (maximum) you must operate so that the air regulation ser
-
vomotor sets to the minimum to perform the control also in this position.
16) To set the air – and thus gas – regulation servomotor to the minimum, set the modulation switch to
MIN .
7) When the air servomotor is set to minimum, and it is necessary to change the combustion conditions (gas/air),
see the instructions for regulating gas valves model MB-VEF...
8) It is advisable to perform the combustion control using the instruments and, if necessary, change the previous
regulation also in some intermediate points of the modulation stroke.
9) Now, check the correct automatic modulation operation.
20) The air pressure switch has the function of locking the control box if the air pressure is not correct. The
pressure switch must thus be set to start by closing the contact (a normally open contact) when air pressure
in the burner reach a sufficient value.
Note that if the normally open contact does not close (insufficient air pressure), the control box performs
its cycle but the ignition transformer does not start, the gas valves do not open and as a consequence,
the burner stops in lock. To check the correct operation of the air pressure switch,
set the burner to the
minimum output, increase the regulation value so as to check when it should start to immediately “lock”
the burner. Unlock the burner by pressing the special push button and restore the pressure switch reg-
ulation to a sufficient value to detect the existing air pressure during the pre-ventilation step.
The pressure switch connection circuit provides for the automatic control; thus, the contact provided to be
closed when at rest (fan off, and thus, absence of air pressure in the burner) must implement this condition,
or the control box does not start (the burner remains off).