baltur SPARKGAS 30 LX, Instruction

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0006080799_200708
2) The gas pressure control switches (minimum and maximum), if installed, have the function of preventing the
burner from operating when gas pressure does not range in the expected values. From the specific function
of the pressure switches, it is evident that the minimum pressure control switch must used the contact that
is closed when it detects a higher pressure than that to which it is set, the maximum pressure control switch
must use the contact that is closed when it detects a lower pressure than that to which it is set. Therefore,
the gas maximum and minimum pressure switch regulation must be performed during the burner general test
and inspection, based on the pressure measured each time. Pressure switches are electrically connected in
series; thus, the start (intended as circuit opening) of any one of the gas pressure switches does not allow
starting the control box and thus, the burner. When the burner is operating (flame on), the start of the gas
pressure switches (circuit opening) causes the immediate shut down of the burner. Upon the general test and
inspection of the burner, it is necessary to check the correct operation of the pressure switches. By suitably
acting on the respective regulation members, make sure that the pressure switch starts (circuit opening), thus
shutting down the burner.
22) In case of UV photoelectric cell, after at least one minute from ignition extract the photoelectric cell from its
housing. When the UV photoelectric cell is extracted from its housing, it cannot “see” the ultraviolet radiation
emitted by the flame and thus, the relevant relay de-energises. The burner immediately shuts down in “lock”.
A light greasiness strongly affects the passage of ultraviolet beams through the UV photoelectric cell bulb, thus
preventing the internal photosensitive element from receiving the necessary radiation for a correct operation.
If the bulb is dirty with light oil, heavy oil, etc., clean it accurately. Note that a simple finger contact can cause
a light greasiness, sufficient to impair the UV photoelectric cell operation. The UV photoelectric cell does not
“see” daylight or the light of a common candle. A possible sensibility check can be made with a flame (lighter,
candle) or with the electrical discharge occurring between the electrodes of a common ignition transformer.
To ensure a correct operation, the UV photoelectric cell current value must be sufficiently stable, and must
not decrease below the minimum value required for the specific control box. Said value is shown in the wiring
diagram. It may be necessary to experimentally search the best position by making the body containing the
photoelectric cell slide (axial or rotation movement) with respect to the fixing clamp.
23) Check the efficiency of the boiler thermostats or pressure switches (their start must shut down the burner).
AIR REGULATION ON COMBUSTION HEAD
(See dr. n°0002933310)
Warning: When, as in this case, the burner is provided with gas valves model MB-VEF...., by moving the air
regulation device on the combustion head there
automatically and unavoidably occurs a gas output
variation (see chapter Valve operation principle, model MB-VEF...).
The combustion head is equipped with a regulation device, so as to open or close the air passage between disk
and head. By closing the passage, it is thus possible to obtain a high pressure upstream of the disk also for low
flow rates. The high air speed and turbulence allows a better penetration of the same into the fuel and therefore,
an excellent mixture and flame stability. It may be necessary to have a high air pressure upstream of the disk, so
as to prevent flame pulses. This condition is indispensable when the burner operates on pressurised combustion
chamber and/or with high heating load. From what said above it is evident that the device closing the air on the
combustion head must be set to such position as to
always obtain, behind the disk, a very high air pressure value.
It is advisable to regulate so as to have such air closure on the head as to require the opening of the air damper
regulating the flow of the burner ventilator suction. Of course, this condition must only occur when the burner is
operating at the maximum desired output.
In practice, the regulation must start with the device that closes the air on the combustion head in an intermediate
position, igniting the burner for an indicative regulation as explained above.
When the
maximum desired output is reached, correct the position of the device closing the air on the combus-
tion head by moving it forwards or backwards so as to have a suitable air flow for the output,
with suction air
regulation damper sensibly open (see dr. n° 0002933310).
N.B. To facilitate the combustion head regulation, see table (dr. n° 0002933191)
When reducing the air passage on the combustion head, avoid closing it completely, which may cause
an excessive heating of the head with a consequent quick deterioration. Perfectly adjust to central posi-
tion with respect to the disk. Note that if not perfectly centred with respect to the disk may cause a wrong
combustion and an excessive head heating, with a consequent quick deterioration.
The check is carried
out by looking through the inspection hole on the rear side of the burner. Afterwards, tighten the screws locking
the position of the air regulation device on the combustion head.