baltur BTG 11P, Instruction

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1) Make sure that the discharge of combustion products can take place freely (chimney lock-gates should be
open) and that there is water in the boiler.
2) Open as much as considered necessary, the combustion air regulator, (see 8920/1) and open by about one
third the air passage between the head and the flame disk (diffuser) (see “Regulation of the combustion Head”).
3) Operate the regulators incorporated in the gas valves in such a way as to obtain the gas delivery presumed
necessary (see 0002910310).
4) Disconnect the 2nd flame thermostat and give current to the burner by opening the main switch.
The burners is then turned on and carries out the pre-ventilation phase. If the air pressure exceeds that value
at which the air pressure switch has been set, the ignition transformer will be connected and, subsequently,
the gas valves (safety and 1
st
flame) will be inserted.
The valves open completely and gas delivery is limited to the position at which the flow regulator incorporated
in the 1
st
flame valve has been manually regulated. At first ignition, successive “shut downs” could occur, due to
the following reasons:
a - The gas pipeline has not been adequately purged of air and therefore the quantity of gas is not sufficient to
allow for a stable flame.
b - A “shut down” with flame presence could be caused by flame instability in the ionisation zone, due to and
incorrect air/gas ratio. This can be remedied by varying the quantity of air and/or gas delivered, in order to find
the correct ratio. It could also be caused by an incorrect distribution of air/gas in the combustion head. This can
be corrected by operating the regulation device of the combustion head by closing or opening more the air
passage between the head and the gas diffuser. See chapter “regulation of the combustion head”.
c - It could happen that the ionisation current is help up by the current discharged from the ignition transformer
(the two currents have to run the same course on the burner’s ”earth”) and so the burner goes to “shut
down” due to insufficient ionisation. This can be remedied by inverting the input (230V side) of the ignition
transformer (change the places of the two wire that take voltage to the transformer). A shut down with flame
presence could also be caused by the burner’s casing not being properly “grounded”. We must point out that
the minimum value of the ionisation current to ensure the working of the control box is shown in the electrical
diagram; normally the ionisation current is decidedly higher. To check the ionisation current, connect a
microammeter with an adequate scale “in series” to the ionisation circuit. The cable of the ionisation electrode
is equipped with a connector (see circuit diagram) to facilitate the micro-ammeter connection. The high
isolation wire that comes from the electrode must be inserted to the negative (sign -) of the microammeter.
5) With the burner on, adapt delivery to that desired (methane gas = 8550 kcal/m
3
) by reading the meter. Take two
readings, the second one exactly one minute after the first one. The difference between the two readings schould
be multiplied by in order to obtain the flow per hour (60 minutes). This output can be modified by operating the
special regulator incorporated in the valve (see the last pages for a desciption of how to regulate the valves).
6) Control that combustion occurs correctly by using the appropriate instruments
(CO
2
= about 10% for methane gas - CO max. = 0.1%).
7) After regulation, turn the burner off and on again several times to check that ignition occurs correctly.
With the burner disconnected from the main switch, connect the 2 nd flame thermostat and regulate the special
device on the servomotor in such a way as to obtain an opening of the air shutter presumed necessary for the
2
nd
flame (see BT 8920/1). Open as well the gas flow regulator incorporated in the valve to allow for the correct
delivery presumed necessary for the 2 nd flame (main flame).
8) Now close the main switch to start up the burner. When the burner has started up it is necessary to check, as
previously shown, the gas delivery and the combustion with the appropriate instruments. When the results are
known, if necessary, proceed with varying the gas delivery and the relative combustion air in order to adapt
delivery to that required for the specific case (boiler potentiality). It is also necessary to check if the CO
2
and CO
values are adequate (CO
2
max. = about 10% for Methane gas and CO = 0.1%).
9) Control the efficiency of the safety devices: the “shut down” (by detaching the ionisation electrode cable), the
air pressure switch, the gas pressure switch, the gas pressure switch and the thermostats).
N.B. The pressure switch is self-controlled and trefore it must close the contact, which is foreseen to be closed
at rest, (fan stops and consequently there is an absence of air pressure in the burner); if it does not, the
control box will not be inserted (the burner remains at as standstill). It must be specified that if the contact is
not closed during working, the control box will carry out its cycle, but the ignition transformer will not be
inserted and the gas valves will not open. Consequently, the burner will go to shut down. Check that the air
pressure switch functions properly with burner operating at 1
st
flame only, increase the regulating value until
it reaches intervention point and the burner should go to shut down. To ublock 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.
NATURAL GAS STARTING UP AND REGULATION
(for LPG operation see the relative chapter)
ENGLISH