baltur 67510010, Installation, Use And Maintenance Instruction Manual

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ENGLISH
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0006160236_201711
• The air pressure switch prevents the opening of the gas valves
if the air pressure is not the foreseen one. The pressure switch
must therefore be adjusted to intervene and close the contact
when the air pressure in the burner reaches a sufficient value. If
the air pressure switch does not detect a pressure greater than
the set one, the equipment runs through its cycle but the ignition
transformer does not switch on and the gas valves do not open, and
the burner therefore “shuts down”. To verify that air pressure switch
is operating correctly, while the burner is ignited on minimum flame,
increase the adjustment value until the pressure switch triggers an
instant “blocked” stoppage of the burner. Set the pressure switch
to a level slightly below the actual air pressure detected at the
minimum operation flame. Release the burner and check that it
starts up correctly.
The gas pressure switches (minimum and maximum) prevent
the burner from operating when gas pressure is not 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.
It is essential to check that the burner is functioning correctly at the
time of the first ignition.
Adjustment before switching on the burner:
regulate the pressure switch for minimum pressure at the minimum
value of the scale, regulate the pressure switch for the maximum
value at the maximum value of the scale.
REGULATION AFTER THE BURNER CALIBRATION:
With the burner running at maximum output, regulate the pressure
switch for minimum pressure by increasing the setting value until the
burner shuts down, read the value on the regulation ring and set it to
a value diminished by 5 mbar.
With the burner running at maximum power, regulate the pressure
switch for maximum pressure, diminishing the regulation value until
the NC (normally closed) contact opens. Read the value on the
regulation ferrule and set it to a value increased by 5 mbar.
The pressure switches are connected so that, the operation (i.e.
opening of the circuit) of one of the switches makes the burner shut
down immediately if it is working (flame lit).