baltur BT 40 MG Instrucciones De Uso página 29

18) The servomotor regulating the flow of the fuel/aír mixture is started up. Wait until the disk with the regulation
screws has turned approximately 120 (that is the space covered by three screws). Then stop modulation by
turning the switch to "0". Visually check the flame and, if necessary adjust the combustion air flow following the
indications given above at point 16. Then check the combustion using the special instruments and, if necessary
modify the adjustments previously made only on the basis of a visual control. The above operation must be
repeated in progressive steps (turning the disk approximately 12° each time) and regulating the fuel/air ratio as
needed during each subsequent step. Make certain that the fuel flow progression is gradual and that maximum
flow is reached only at the end of the modulation stroke. This is an essential condition for gradual modulation.
lf necessary modify the position of the screws controlling the fuel flow in order to achieve this condition.
With any given air/fuel ratio, the correct the carbon dioxide (CO
should be on the order of at least 10% at minimum flow and reach an optimal value of approximately 13% at
maximum flow). It is advisable never to exceed a C0
excess air which could, in turn, cause a marked increase in the smoke index subsequent to inevitable conditions
(i.e. variations in atmospheric pressure, presence of small deposits of dust in the fan air duct, etc.).
The smoke index is strictly related to the type of fuel used (the latest regulations in this area indicate no. 2 on
the Bacharach scale as maximum acceptable level). It is advisable to keep the smoke index at a reading lower
than no. 2 on the Bacharach scale even though the CO
It must be recalled to regulate properly the system water temperature must have reached the set point and that
the burner be operating for at least fifteen minutes. lf the appropriate instruments are not available flame
colour is used as indicator. Regulate so that the flame is a clear orange colour; do not create either a red flame
with smoke or a white flame with an exaggerated amount of excess air. After having made certain that the air/
fuel regulation is correct, tighten the screws locking the regulation screws in place.
19) Now check that the automatic modulation is functioning properly by turning the "AUT0-MAN" switch to the
"AUT" (automatic) position and the "MIN-0-MAX " switch to the "0" position. In this manner modulation is only
activated by the automatic signal coming from the boiler probe.
CHECKS
Once the burner has been turned on, the safety devices (photoelectric cells, lockout, thermostat) must be
checked.
1) The photoresistance are flame control devices and if the lame cuts out during operation, they are tripped (this
control should be performed after the flame has been on for at least one minute).
2) lf the flame does not ignite within the time limit set by the control box, the burner must be able to revert to the
lockout setting and remain there. Lockout cuts off the fuel supply and then shuts down the burner, turning on
the lockout warning light. To ensure that the photoresistance and lockout are functioning properly, proceed as
a) Start up the burner.
b) At least one minute after ignition has taken place, withdraw the photoresistance from its housing. This
simulates the no-flame condition, blacking out the photoresistance (use your hand or a rag to cover the
window in the photoresistance support). The burner flame should go out and the unit should revert to
lockout conditions. The unit can only be reset manually by pressing the special button. The lockout efficiency
test must be performed at least twice.
3) To check thermostat efficiency, run the burner until the water in the boiler reaches a temperature of at
least 50° C. Then turn the thermostat control knob to lower the temperature set point until the thermostat trips
and the burner is simultaneously shut down. The thermostat should trip at a temperature within 5 ÷ 10° C of the
set point for the control thermostat (boiler thermostat); if this is not the case regulate the thermostat setting so
that it corresponds to that of the thermostat.
) value will increase as the flow increases (it
2
value of 13%; this will prevent operating with limited
2
reading could be slightly lower as a result.
2
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