baltur BGN 100 DSPGN, Инструкция по эксплуатации

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17) The air pressure switch has the job of bringing the control box to a safety shut down if the air pressure is not at
the correct value. Therefore, the air pressure switch must be regulated in such a way as to intervene by closing
the contact (foreseen to by closed while working) when the air pressure in the burner has reached a sufficient
level. The pressure switch is self-controlled and therefore it must close the contact (fan stops and consequently
there is an absence of air pressure in the burner) if it does not, the control box will be inserted (the burner remains
at a stadstill).It must be specified that if the contact is not closed during working (insufficient air pressure), the
control box will carry out its cycle, but the ignition transformer will not be inserted and the gas pilot valves will not
open. Consequently, the burner will go to "shut down". Check that the air pressure switch functions properly with
burner at minimum delivery, increase the regulating value until it reaches intervention point and the burner should
go to shut down. To unblock the burner, press the special push-button and return the pressure switch regulator to
a sufficient value in order to measure the air pressure existing during the pre-ventilation phase.
18) The pressure switches which control the gas pressure (minimum and maximum) have the job of stopping the
burner functioning when the gas pressure is not within the values specified. From the specific functions of the
pressure switches, it is evident that the pressure switch controls the minimum pressure must make use of the
contact, which is closed, when it measures a pressure which exceeds that at which it has been set.
The maximum pressure switch must make use of the contact, which is closed, when it measures a pressure
below that at which it has been set. The minimum and maximum gas pressure switches should be regulated
during the burner's general inspection and should be in function with the pressure found each time.
The pressure switches have been electrically connected in series and therefore theintervention (by this we mean
the opening of the circuit) of any one of the gas pressure switches, will prevent the control box and thus the
burner from starting up. When the burner is operating (flame lit), the intervention of the gas pressure switches
(opening of the circuit) determines the immediate arrest of the burner. During the burner's general inspection,
check the correct functioning of the pressure switches. By operating the respective regulating device, it is
possible to control the pressure switch's intervention (opening of circuit) which causes the burner's arrest.
19) Check the efficiency of the flame detector (ionisation electrode) by detaching the wire coming from the electrode
and by turning on the burner. The control box should carry out completely its cycle and two seconds after the
ignition flame (pilot) is formed, it should go to "shut down". This control should also be carried out when the
burner is already operating. By detaching the wire that comes from the ionisation electrode, the control box
should go immediately to "shut down".
In the case of the UV photoelectric cell, slide the wire out of its seat on the burner and verify the "shut down".
20) Check the efficiency of the boiler thermostats and pressure switches (this should result in the burner coming to
a standstill).
ADJUSTEMENT OF THE AIR FLOW TO THE BURNER HEAD (see BT 8769/1)
The burner head is fitted with a regulator control, which closes or open the air passage between the disk and the head.
By closing the air passage, a high pressure on the disk can be achieved, for low rates as well. The increased speed and
turbulence of the air makes it penetrate with increased force, thus giving a better mixture and greater flame stability.
It may be essential to have high air pressure at the disk, to stop flame pulsation. This condition is practically indispensable
when the burner is working on a pressurized boiler and/or a high thermic load. It is clear from the above description that
the device that closes the air to the burner head must be taken to a position where it always obtains a level behind the
disk that is much higher than the air pressure level. It is recommended to set the device with the air to the head closed
off, so that a sizable opening is required on the air shutter that controls the flow to the burner fan intake.
Obviously, this condition must occur when the burner is working at the maximum desidered delivery rate.
In practice, the setting operation shuld be started with the device that closed the air to the burner head at an intermediate
position, and the burner should be started up for a trial setting procedure, as described previously.
When the maximum desired delivery rate is reached, adjust the position of the device that closes the air to the burner
head, moving it forwards or backwards in order to achieve an adequate air flow in delivery, with the intake air control
shutter well open. When reducing the size of the air passage to the burner head, avoid closing it completely.
Ensure that the burner head is perfectly centered in relation to the disk. If it is not perfectly centered, the flame may burn
badly and overheat the head, causing rapid deterioration. The centering can be checked by looking from the inspection
hole on the rear part of the burner and then fully tightening the screws (if present) that hold in position the device that
controls the air flow to the burner head.
N.B. Check that the ignition occurs in a regular manner; if the passage between the head and the disk is closed, it may
occur that the speed of the mixture (combustible air) is so high that ignition is made difficult. If this occurs, then the
regulator must be opened gradually until it is in a position where the ignition occurs in a regular manner, and this
position must be accepted as the set position. Remember that, for the first flame, it is preferable to limit the
quantity of air to the bare minimum necessary for a safe ignition, even in the most demanding cases.