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0006080764 _201312
ENGLISH
NATURAL GAS STARTING
UP ANd REGULATION
• It is indispensable to carry out a purge of the air contained in
the pipeline, if it had not been carried out when connecting the
burner to the gas pipeline. As a precaution, special care should
be taken and doors and windows should be opened. Open the
union on the pipe near the burner and then open the gas on/off
cocks a little way. Open the pipe union on the pipeline situated
near the burner and then open a little the cut-off cock (or cocks).
When the characteristic odour of gas can be smelled, close the
cut-off cock. Wait until the gas present in the room has dispersed,
and then reconnect the burner to the gas pipeline. Subsequently,
re-open the gas cut-off valve.
• Check that there is water in the boiler and that the gates on the
system are open.
• Check, with absolute certainty that the discharge of combustion
products can take place freely (boiler and chimney lock-gates
should be open).
• Make sure that the voltage of the electric line to which the burner
is to be connected, corresponds to that required by the burner
and that the electrical connections (motor or principle line)
have been prepared to match the voltage rating available. Also
check that all electrical connections made on-site are performed
correctly as shown in our wiring diagram.
• Make sure that the combustion head enters the furnace to the
extent specified by the boiler manufacturer.
• Remove the protection cover from the disk carrying the air and
gas flow regulator screws and slacken the screws that block
the regulator screws.
• Check that the air regulator device on the combustion head is in
the correct position based on the required fuel throughput (the air
passage between the diffusor disk and the head must be small
for low throughput and relatively wide when throughput is higher).
Refer to the chapter “Air regulation on the combustion head”.
• Fit a pressure gauge of appropriate scale to the pressure intake
on the gas pressure switch (if the amount of pressure to be used
allows it, we recommend to use a water column instrument; do
not use instruments with indicator hands for low pressures).
• Open the flow regulator integrated in the ignition pilot flame valve
as necessary. Also check that the combustion airflow control
shutter is sufficiently open; if necessary, alter the position by
acting on the regulator screws on the regulator disk. If necessary,
adjust by acting on the adjustment disc screws on regulation disc.
• With burner switch to “O” and main switch turned on, check
that the fan motor revolves in the correct direction. If necessary,
change the position of the two cables in the line that feeds the
motor in order to reverse the direction of revolution.
• Now turn the panel switch on and turn modulator switches to
the MIN (minimum) and MAN (manual) position. This powers
on the control device, and the programmer turns on the burner
as described in the chapter “Operation description”.
During pre-ventilation, make sure that the air pressure
switch changes its status (from the closed position without
pressure measurement to the closed position with pressure
measurement). If the pressure switch does not detect sufficient
pressure (and does not change status), neither the ignition
transformer nor the pilot flame gas valve are activated and the
equipment shuts down. However, an occasional lock-out during
the first stage of ignition is normal, as air is still present in the
valve train pipeline. The air must be vented to obtain a stable
flame. To release, press the “reset” key.
• UV PHOTOCELL
I f t h e f l a m e i s d e t e c t e d b y t h e U V
p h o t o c e l l r e m e m b e r w h a t s p e c i f i e d b e l o w.
A slight amount of grease will strongly compromise the passage
of the ultraviolet rays through the UV photocell bulb, preventing
the internal sensitive element from receiving the quantity of
radiations required for proper operation. If the bulb is fouled
with diesel fuel, fuel oil, etc., it must be properly cleaned. Even
contact with the fingers can leave a slight greasy film, enough
to affect the function of the UV photocell. The UV photocell does
not “see” daylight nor does it perceive the light of an ordinary
lamp. Sensitivity can be checked with a flame (cigarette lighter,
candle) or with the electric discharge between the electrodes of
a common ignition transformer. To ensure a proper operation, the
UV photocell current value must be sufficiently stable and not go
below the minimum value required for the specific equipment.
It may be necessary to tentatively find the best position by
sliding (axial or rotational movement) the casing that contains
the photocell with respect to the fastening clamp. This can be
checked by connecting a micro-ammeter, with a suitable scale,
in series to one of the two UV photocell connection cables.
Obviously the polarity (+ and -) must be respected. The minimum
cell current value, to ensure the correct operation of the control
box, is shown on the wiring diagram.
• As soon as the burner is ignited at low flame (main flame valve
open and modulator on minimum) make a visual inspection of the
strength and appearance of the flame, making any corrections
required (adjust the gas or air regulator screws on the modulating
disk). The next step is to take a meter reading of the volume of
gas put through the burner (see the “Meter Reading” section).
If necessary, a further correction in the gas flow may be made
as described above. Then check the combustion with the
suitable instruments. To obtain a correct air-to-gas ratio, the
value of carbon dioxide (CO
2
) should increase in proportion to
an increase in supply. This value is approximately for methane,
at least 8%, at minimum fuel delivery to the burner, up to an
optimum value of 10% at maximum fuel delivery. We recommend
that the value of 10% should not be exceeded, as operation
in too limited an excess of air can give rise to unacceptable
carbon monoxide (CO) levels (due to variations in atmospheric
pressure, or dust deposits in the air lines). It is necessary to
use a suitable instrument to check that the carbon monoxide
(CO) percentage in the smoke does not exceed the maximum
allowed value of 0.1%
• After having regulated gas throughput for the minimum flame
setting, set the modulation switches to “MAN” (manual) and
“MAX” (maximum).