baltur TBG 35 MC, Installation, Use And Maintenance Instruction Manual

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ENGLISH
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MODULATION OPERATION DESCRIPTION
When the burner is on at minimum flow rate, if the modulation pro-
be requires it (set to a temperature or pressure value higher than
that in the boiler) the air/gas regulation servomotor starts turning;
• in a clockwise direction the air flow increases;
• anticlockwise rotation: the air flow decreases.
thus gradually increasing gas supply and combustion air until the
maximum supply level set for the burner is reached. The burner
remains in the maximum flow position until the temperature or
pressure is high enough to trip the modulation probe, which rever-
ses the direction of rotation of the air regulation servomotor. The
inverse rotation and therefore the air and gas supply reduction
occurs shortly thereafter. With this procedure, the modulation
system attempts to balance the amount of heat supplied to the
boiler with respect to the amount the boiler releases for use. The
modulation probe installed on the boiler measures any request
variation and automatically adjusts fuel and the air/gas supply with
an increasing or reducing rotation. If the limit value (temperature
or pressure) at which the stop device is set (thermostat or pressu-
re switch) is reached even with gas supply at minimum level, the
burner is shut down by the device. As the temperature or pressure
drops below the shut-down device's set point, the burner will be
turned on again as described above.
AIR REGULATION ON THE COMBUSTION HEAD
The combustion head has a regulation device that allows the air
passage between the disc and the combustion head to be ope-
ned or closed. Closing the passage, you can obtain high pressure
upstream of the disc even at low flow rate. The high speed and
turbulence of the air provides for its greater penetration into the
fuel and therefore an excellent mixture and flame stability. High
air pressure upstream of the disc may be necessary to prevent
flame fluctuations, this is particularly essential when the burner
works on the combustion chamber that is pressurised and/or at a
high thermal load.
The device closing the air on the combustion head must be set to
such position as to always obtain, behind the disc, a very high air
pressure value. When the burner works at its maximum output,
regulate the air closure on the combustion head in such a way
that there is a generous opening of the air shutter regulating the
air flow. Therefore start the regulation with the device that closes
the air on the combustion head in an intermediate position, igniting
the burner for an indicative regulation as explained above. Move
the combustion head forward or backward to obtain an air flow
adequate for the output.
CAUTION / WARNING
Check that the combustion head is centred with respect to
the disk. An imperfect centring could cause a poor combu-
stion and overheating of the head with its subsequent rapid
deterioration.
BURNER X
Value indicated by
index 4
TBG 35 MC 3 ÷ 31 0 ÷ 6
• Loosen the screw (1)
• Turn screw (2) to position the combustion head (3), referring to
index (4)
• Adjust the distance (x) between the minimum and maximum
according to the indications in the table
CAUTION / WARNING
The above adjustments are indicative only; position the
combustion head according to the characteristics of the
combustion chamber.