baltur BGN 40 P Mode D'emploi page 43

b) A "shut down" with flame presence may be caused by flame instability in the ionization zones due to an incorrect
air/gas ratio. This can be remedied by varying the quantity of air and/or gas delivered in such a way as to find the
correct ratio. It could also be caused by an incorrect distribution of air/gas in the combustion head. Correct this
by operating the combustion head regulating device (close more or open more the air passage between the
head and the gas diffuser).
c) It could happen that the ionization current is held up by the discharge current of the ignition transformer (the two
currents have to run the same course on the burner's earth) and so the burner goes to "shut down" due to
insufficient ionization. This can be remedied by inverting the input (230V side) of the ignition transformer (change
the places of the two wires that take voltage to the transformer). A shut down can also be caused by the burner's
casing not being properly grounded. The minimum value of the ionization current to ensure the working of the
control box is shown on the specific electrical diagram.
8) With the burner lighted to the minimum, it is necessary to visually check the entity and appearance of the flame
immediately, and make the necessary corrections by adjusting the gas and air supply regulators (see points 4
and 5). Subsequently, read the meter to check the quantity of gas supplied. If necessary, correct the gas and
combustion air supply by proceeding as described above (points 4 and 5). Then check the combustion using the
special instruments provided for the purpose. For a correct gas/air ratio, the carbon dioxide (CO2) value for methane
must be at least 8%, or O2 = 6% at minimum supply to the burner, up to an optimum value of 10% or O2 = 3% for
maximum supply.
It is essential to check the percentage of carbon monoxide (CO) present in the fumes, to ensure that it does not
exceed the maximum permitted value of 0.1% (1000 ppm).
9) Repeatedly check to ensure that ignition of the first flame occurs correctly. After adjusting functioning with the first
flame, switch off the burner, turn off the main switch and close the electric circuit that controls the ignition of the
st
second flame. (The 1
10) Open the gas flow manual regulator to the extent necessary for the second flame (main flame).
11) Switch on the burner again by turning on the main switch and the appliance switch. The burner lights up and
automatically ignites the second flame (main flame). Visually check the entity and appearance of the flame immediately,
making the necessary corrections by adjusting the gas and air supply regulators as described at points 4 and 5.
12) Adjust the flow regulator suitably for the second flame to suit the specific case. Avoid keeping the burner in
operation if the flow rate is greater than the maximum value permitted for the boiler. To prevent possible damage to
it, it is therefore advisable to switch off the burner immediately after two meter readings.
13) Subsequently, with the burner at the maximum supply required for the burner, check the combustion using the
instruments provided, and modify, if necessary, the adjustment made earlier (air, and gas, if necessary) by means
of visually checking only (CO2 max. = 10%; O2 min. = 3%; CO max. = 0.1%).
14) The air pressure switch has the function of preventing opening of the gas valve if the air pressure is incorrect. The
pressure switch must therefore be adjusted to operate by closing the contact when the pressure of air in the burner
reaches a sufficient value. The connecting circuit of the pressure switch involves self-control; therefore, it is necessary
that the contact provided for closing with the fan stopped (absence of air pressure in the burner) actually brings
about this condition. Otherwise the control box is not activated (the burner remains stopped). If the air pressure
switch does not measure a pressure higher than the calibration value, the equipment performs its cycle, but does
not activate the ignition transformer and the gas valves do not open; therefore, the burner is stopped by "lock-out".
To ensure correct working of the air pressure switch, it is necessary to increase the regulation value, with the
burner lighted, with only the first flame, resulting in the action that will be immediately followed by the burner
stopping in "lock-out". Restart the burner by pressing the push-button provided, and adjust the pressure switch to
restore the pressure to a value sufficient for measuring the air pressure existing during the pre-ventilation phase.
15) The gas pressure control switches (minimum and maximum) have the function of preventing the burner from
functioning when the air pressure is not within the required values. From the specific function of the pressure
switches, it is quite clear that the minimum pressure control switch must use the contact that is closed when the
pressure switch measures a pressure higher than that for which it is adjusted. The maximum pressure switch must
use the contact that is closed when the pressure switch measures a pressure lower than the one for which it is
adjusted. Regulation of the minimum and maximum pressure switches must therefore occur when the burner
starts operating depending on the pressure encountered every so often. The pressure switches are electrically
connected in series; therefore the action (understood as opening of the circuit) of the gas pressure switches does
not allow the appliance to be activated. It must be specified that the action (understood as opening of the circuit) of
any one of the pressure switches, when the burner is operating (flame on) immediately causes the burner to stop.
On first ignition of the burner, it is essential to check that the pressure switches are working correctly. The respective
regulation controls can be used to check the action of the pressure switch (opening of the circuit) which causes the
burner to stop.
42
nd
and 2 stage switch must be in the 2
nd
stage position.)
EN