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REGULATION OF AIR AT THE COMBUSTION HEAD (see BT 8608/1)
The combustion head is fitted with a regulation device that closes (moves forward) or opens (moves back) the air gap
between the disc and the head. In this way, when the gap is closed high pressure can be obtained upstream of the
disc, even with low delivery. The high speed and turbulence of the air allows it to penetrate the fuel better, creating an
excellent mixture and providing a stable flame. It may be essential to have a high air pressure upstream of the disc to
prevent the flame from flickering. This is practically indispensable when the burner is working in a pressurised firebox
and/or at high thermal loads. Therefore, it is clear that the device that shuts off the air at the combustion head must be
positioned in such a way as to always keep the air pressure behind the disc at a significantly higher level.
It is advisable to adjust it in order shut off the air to the head, so that the air lock controlling the intake for the fan opens
significantly. Obviously, this must be checked when the burner is working at the maximum delivery required. In practice,
regulation must begin using the device that closes the air to the combustion head in an intermediate position, and the
burner must be ignited to allow regulation as described above.When the maximum delivery required has been
reached, the position of the device that shuts off the air to the combustion head must be corrected, by moving it
forward or back to provide an adequate air flow with the air lock for the air intake, considerably open. When reducing
the air passage in the combustion head, care must be taken not to close it altogether. Make sure it is perfectly centred
in relation to the disc.
If it is not properly centred on the disc, poor combustion and overheating of the head could occur, resulting in its rapid
deterioration. This check is made by watching the LED on the back of the burner and then tightening the screws that
lock the regulator for the air to the combustion head, in position.
N.B. Make sure that ignition occurs correctly because if the regulator has moved forward the speed of the air coming
out may be so high that it makes ignition difficult. If this should occur, move the regulator further back a little at
a time, until a position is reached where ignition occurs regularly, and accept this as the permanent position.It is
preferable to limit the amount of air for the 1st flame to as little as possible, to ensure ignition, even under the
most demanding conditions.
MAINTENANCE
At the end of the heating season it is normally advisable to clean the gas and heavy oil filters, the combustion head
(disk, insulators and nozzles), the combustion air passage and UV photo-electric cell.
Great care should be taken during re-assembly to ensure that the electrodes do not discharge to ground or short
circuit, which would cause the burner to lock out.
To cleaning nozzle passages, use soft material such as wood and plastic.
It is advisable to replace nozzles every 12 months of working