baltur TBML 450LX ME, Instruction Manual For Installation, Use And Maintenance

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AIR PRESSURE SWITCH FUNCTIONAL DESCRIPTION
The air pressure switch stops the equipment operation if air pressure
is not at the expected value.
The pressure switch must therefore be adjusted so that it is triggered
to close the NO (normally open) contact when the air pressure in the
burner reaches a particular value.
If the air pressure switch does not detect a pressure greater than that
calibrated, the equipment runs through its cycle but does not switch on
the ignition transformer and does not open the gas valves and so the
burner “locks-out”.
To ensure the air pressure switch correct operation, with burner at the
minimum output, increase the adjustment value until reaching the trig-
gering value which must be followed by the immediate burner lock-out.
To unblock the burner, press the special pushbutton and return the
pressure switch regulator to a sufficient value in order to measure the
air pressure existing during the pre-ventilation phase.
Air pressure sampling point is upstream the air dampers.
GAS PRESSURE SWITCH OPERATION DESCRIPTION
The gas pressure control switches (minimum, maximum and sealing
test) 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 pres-
sure higher than its own setting.
The maximum pressure switch uses the NC (normally closed) contact
that is closed when the pressure switch detects a pressure lower than
the value it is set to.
Adjustment of minimum and maximum pressure values on the pressu -
re switches must be performed when testing the burner, on the basis of
the pressure measured in each case.
There is also the valve sealing check pressure switch, which stops
the burner when there is a leakage in one of the two valves during the
initial check phase.
The triggering (opening of the circuit) of any of the pressure switches
when the burner is running (flame on) locks out the burner immediately.
When first switching on the burner it is essential to check that they
work properly.
REGULATION BEFORE IGNITING THE BURNER:
With the burner running at maximum power, regulate the pressure swi -
tch for minimum pressure by increasing the regulation value until the
burner shuts down, read the value on the regulation ring nut and set it
to a value diminished by 20 %.
With the burner running at maximum power, regulate the pressure swi -
tch for maximum pressure, diminishing the regulation value until the
NC (normally closed) contact opens. Read the value on the regulation
ring nut and set it to a value increased by 20 %.
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