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STARTING UP AND REGULATION WITH METHANE GAS
1)
Make sure that the combustion head enters 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 “Regulation of the Combustion Head”:
2)
If not already done so 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 then open a little the gas cut-off cock (or cocks).
When the characteristics 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.
3)
Check that there is water in the boiler and that the system’s gate valves are open.
4)
Check, with absolute certainty, that the discharge of combustion products can take place freely (boiler and
chimney lock-gates should be open).
5)
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 and principle lines) have been prepared to
match the voltage rating available.
Check that all the electrical connections carried out on the spot are in accordance with our electric wiring
diagram.
Open the circuit between the terminal boards n° 19 and 26 by taking away the “bridge” (see the wiring giagram)
in order to avoid the connection of second flame, while acting to regulate the first flame.
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 instrument, do not use a pointer instrument for moderate pressure) to the pressure plug on the
gas pressure switch.
7)
Regulate the air for the second flame.
(See the specific instructions for the air butterfly valve regulation shown on page BT 8606).
8)
By operating the regulating devices of the gas valve, open, to the amount considered necessary, the flow
regulator of the 1st flame (see instructions with regard to specific two-stage gas valve model fitted on the burner).
Obviously, if there is a flow regulator for the safety valve, it should be opened completely too.
10)
Now insert the switch on the commend panel.
The control box receives voltage in this way and the programmer turns on the burner as described in Chapter
“Description of Operations”.
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 valves will be inserted and the control box will go to “shut down”.
Successive “shut downs” can occur during the first ignition phase due to the following reasons :
a)
The gas pipeline has not been sufficiently expelled of air and therefore there is not enough gas present
to permit a stable flame.
b)
A “shut down” with flame presence may be caused by flame instability in the ionisation zone, due to an
incorrect air/gas ratio. This can be remedied by varying the quantity of air and/or gas delivered in such
a way as to find the correct ratio.
It could also be caused by an incorrect distribution of air/gas in the combustion head. Correct this by
operating the combustion head regulating device (close more or open more the air passage between the
head and the gas diffuser).
