baltur BGN 450 ME, Installation, Use And Maintenance Instruction Manual

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ENGLISH
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To ensure correct operation of the air pressure switch you must,
with burner on and in 1st stage, increase its regulation value until
the burner triggers and then it immediately “locks-out”.
Reset the burner by pressing the appropriate button and readjust
the pressure switch to a value that allows you to detect the air
pressure during the preventilation stage.
The gas pressure control switches (minimum and maximum)
prevent the burner from operating when gas pressure does not lie
between the expected range.
The minimum value pressure switch makes use of the NO
(normally open) contact which is closed when the pressure switch
detects a pressure higher than its own setting.
The maximum pressure switch makes use of the NC (normally
closed) contact which is closed when the pressure switch detects
a pressure lower than its own setting.
Adjustment of minimum and maximum pressure values on the
pressure switches must be performed when testing the burner, on
the basis of the pressure measured in each case.
The triggering (opening of the circuit) of any of the pressure
switches when the burner is running (flame on) causes the burner
to stop immediately.
The triggering (opening of the circuit) of any of the pressure
switches when the burner is running (flame on) causes the burner
to stop immediately.
When first switching on the burner it is essential to check that it
works properly.
Verify the flame detector operation as follows:
• Disconnect the wire coming from the ionisation electrode;
• Start up the burner;
• The control box will complete the control cycle and after two
seconds will lock the burner due to the lack of ignition flame;
• switch off the burner;
• Re-connect the wire to the ionisation electrode.
• This test should be carried out with the burner already on; the
apparatus should lock out immediately when the wire from the
ionisation electrode is disconnected.
• Check for the efficiency of the thermostats or boiler pressure
switches (they should shut down the burner when triggered).
CAUTION / WARNING
Check that the ignition takes place properly. In the event
that the mixer is too far forward, it may happen that the
outgoing air speed is so high that ignition is difficult. If this
happens, the mixer must be gradually shifted back until it is
in a position in which ignition occurs normally, and this new
position can be regarded as the final position. Remember
that with a small flame, it is better to limit the amount of
air to the amount strictly indispensable to ensure safe
ignition even in the most difficult cases.
IONISATION CURRENT MEASUREMENT
The maximum ionisation current value required for a correct
operation of the equipment is indicated in the wiring diagram.
The burner provides a significantly higher current and therefore
does not normally require any checks at all.
Should however, the ionisation current need to be measured,
a microammeter must be connected in series to the ionisation
electrode lead by opening the connector as illustrated in the figure.