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small change of the position of the primary air control flap leads to
sensible variation of the primary air flow rate and consequently the
intensity of the pyrolisis process – it is highly recommended to change
the position of the flap with small steps (for example 1mm);
o
The secondary air flow rate is controlled by changing the position of
the primary air control flap –at decreasing the primary air flow rate the
secondary air flow rate is increased and vice versa. The air is directed
in from the distribution box to the burner’s nozzle, where it is preheated
and afterwards mixed with the volatile gases at the burner’s nozzle;
The total air flow rate, drawn in, is controlled by the position of the flap,
which is installed at the air entrance of the air distribution box of the boiler.
The position of this flap is controlled with the lever of the thermovalve of
the boiler. The adjustment of the air flow rate for achieving efficient
combustion process should be done by trained and authorized technician by
measuring the operating parameters of the flue gases with gas-analyzer.
The practice shows that event if the combustion process of the boiler has
been adjusted, after passing some time new settings (i.e. new adjustment)
will be required, because a lot of operating parameters could be changed –
for example the fuel has been changed, changing the thermal capacity of
the boiler and/or heating system, chimney’s operating conditions, etc.
considering that, the following information will be helpful for not trained
person to make appropriate adjustment of the operating parameters of the
boiler in order to achieve high efficiency and optimal fuel utilization.
As primary step of the combustion process operating parameters
adjustment, it is necessary to perform visual inspection of the flame – this
is done by opening the door of the combustion chamber and seeing the
shape and the color of the flame, after that the door should be closed.
EXPLANATION: at opening the door of the combustion chamber, the
static pressure in this chamber will be immediately changed, which will
influence the combustion process (practically the combustion chamber
operates at pressure, which is lower than the atmospheric one), that’s why
it is necessary to make fast observation of the flame in the combustion
chamber, before the ambient air penetration to make influence on the
thermal process.
The flame, getting out of the burner’s orifice is directed downwards and
should reach the ceramic flue gases directing element, positioned in the
combustion chamber of the boiler. The color of the flame at nominal
operating conditions and optimal combustion process (i.e. the process is
