baltur COMIST 122 DSPGM, Instruction

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1) If not already done at the moment of connecting the burner to the gas pipeline, it is indispensable to carry out
a purge of the air contained in the pipeline. As a precaution, special care should be taken and doors and
windows should be opened. Open the pipe union on the pipeline situated near the burner and the open a little
the gas cut-off cock (or cocks). When the characteristic odour of gas can be smelled, close the cut-off cock.
Wait until the gas present in the room has dispersed, and then reconnect the burner to the gas pipeline.
Subsequently, re-open the gas cut-off cock.
2) Check that there is water in the boiler and that the system’s gas valves are open.
3) Check, with absolute certainty that the discharge of combustion products can take place freely (boiler and
chimney lock-gates should be open).
4) Make sure that the voltage of the electric line to which the burner is to be connected, corresponds to that
required by the burner and that the electrical connections (motor or principle line) have been prepared to
match the voltage rating available. Also check that all the electrical connections carried out on the spot are in
accordance with our electric wiring diagram.
5) Make sure that the combustion head is long enough to enter the furnace to the extent specified by the boiler
manufacturer. Check that the device which regulates the air on the combustion head is in the position considered
necessary for the fuel delivery required (air passage between the disk and the head should be considerably
reduced when the fuel delivery is reduced; on the other hand, when the fuel delivery is fairly high; the air
passage between the disk and the head should be relatively open). See chapter “Air Regulation on the
Combustion Head”.
6) Apply a manometer with an adequate scale (if the entity of pressure forecast allows it; it is preferable to use a
column of water instruments, do not use a pointer instrument for moderate pressure) to the pressure plug on
the gas pressure switch.
7) Open, to the quantity considered necessary, the flow regulator incorporated in the ignition flame valve(s)
(pilot). If the burner is already working on light oil fuel, the combustion air regulation shutter must not be
modified; in such a case it will be necessary to adjust the gas flow to the amount of air already adjusted for the
light oil operation. If the burner is started up only on gas it is necessary to verify that the combustion air
regulation shutter is in the right position and, if not, to modify it by operating the adjustable screws of the
regulating disk.
8) Remove the protective cover from the disk on which are inserted the screws which regulate the gas and air
delivery, and unloosen the locking screws.
9) With the switch on the burner’s control panel in the “O” position and the main switch inserted check by manually
closing the relay, that the motor rotates in the right direction. If it does not, exchange the places of two cables
of the motor’s supply line in order to invert its sense of rotation.
10) Now insert the switch on the commend panel and put the modulating switches in the MIN (minimum) and MAN
(manual) positions. The control box receives voltage in this way and the programmer turns on the burner as
described in Chapter “Description of Operations”.
Note: Pre-ventilation is carried out with air open and, during this phase, the servomotor regulating the delivery
(gas/air) is inserted and completes the whole opening run until it reaches the “maximum” position.
Subsequently, the servomotor which regulates delivery (gas/air) returns to the starting position (minimum).
Only when modulation has returned to the “minimum” position, does the control box proceed with its ignition
programme and insert the transformer and the gas ignition valves (pilot). During the pre-ventilation phase
check that the air pressure switch effects a changeover (it should pass from a closed position without
measurement of pressure to a closed position with measurement of air pressure).
If the air pressure switch does not measure sufficient pressure (it will not effect the changeover) and neither
the ignition transformer nor the gas ignition flame valves will be inserted and the control box will go to “shut
down”. It should be pointed out that “shut downs” during the first ignition phase are considered normal. This
is because air still exists in the pipeline of the valve incline and must be expelled before it is possible to have
a stable flame. To unblock the control box, press the relative pushbutton.
STARTING UP AND REGULATION WITH METHANE GAS