31
20152093
GB
Start-up, calibration and operation of the burner
6.6
Adjusting the burner
The optimum adjustment of the burner requires an analysis of
flue gases at the boiler outlet.
Adjust in sequence:
Ignition output
Maximum output
Minimum output
Intermediate outputs between the two
Air pressure switch
Maximum gas pressure switch
Minimum gas pressure switch
Ignition output
According to standard EN 676.
Burners with MAX output up to 120 kW
Ignition can occur at the maximum operation output level.
Example:
max. operation output: 120 kW
max. ignition output: 120 kW
Burners with MAX output above 120 kW
Ignition must occur at a lower output than the max. operation
output.
If ignition output does not exceed 120 kW, no calculations are
required. If ignition output exceeds 120 kW, the regulatory
standard sets that the value be defined according to the
control box safety time "ts":
for "ts" = 3s, ignition output must be equal to or lower than 1/3
of max. operation output.
Example
MAX operation output of 600 kW.
Ignition output must be equal to or lower than:
•
300 kW with ts = 2 s.
•
200 kW with ts = 3 s.
In order to measure the ignition output:
disconnect the plug-socket 7)(Fig. 5) on the ionisation
probe cable (the burner will fire and then go into lockout
after the safety time has elapsed);
perform 10 consecutive ignitions with lockouts;
read the quantity of burned gas on the meter:
this quantity must be equal to, or lower than, the quantity
given by the formula, for ts = 3s:
Example
for G 20 gas (10 kWh/Nm
3
):
ignition output 600 kW
corresponding to 60 Nm
3
/h.
After 10 ignitions with a lockout, the delivery indicated on the
meter must be equal to or less than:
60: 360 = 0.166 Nm
3
.
MAXIMUM OUTPUT
Maximum output must be selected within the firing rate range
shown on page 10. In the above instructions we left the
burner running at the MIN output.
Now press the “increase output” button 2)(Fig. 32 on
page 32), and keep it pressed until the servomotor has
opened the air damper and the gas butterfly valve.
Adjustment of gas delivery
Measure the gas delivery on the meter.
A rough indication can be obtained from table Tab. F on
page 11; just read the gas pressure on the pressure gauge
(see Fig. 35 on page 33) and follow the indications given on
page 11.
–
If it needs to be reduced, decrease outlet gas pressure; if it is
already very low, slightly close the VR adjustment valve.
–
If it needs to be increased, increase the regulator outlet gas
pressure.
Adjustment of air delivery
Progressively adjust the end profile of cam 4)(Fig. 33 on
page 32) by turning the screws 7).
Turn the screws clockwise to increase air delivery.
Turn the screws anticlockwise to reduce air delivery.
MINIMUM OUTPUT
MIN output must be selected within the firing rate range
shown on page 10.
Press and hold the “output reduction” button 2)(Fig. 32 on
page 32) until the servomotor closes the air damper and the
gas butterfly valve is at 65° (factory setting).
Adjustment of gas delivery
Measure the gas delivery on the meter.
–
If it is necessary to reduce it, slightly decrease the angle of
cam III) (Fig. 34) with small, regular movements, i.e. bring it
from an angle of 65° to 63° - 61°...
–
If it is necessary to increase it, lightly press the “output
increase” button 2)(Fig. 32) (open the gas butterfly valve by
10-15°), and increase cam III angle (Fig. 34) with a series of
small movements, i.e. move from angle 65° to 67° - 69°...
Now press the “power reduction” button until the servomotor
returns to the minimum opening position, and measure the
gas delivery.
NOTE:
The servomotor follows the adjustment of cam III only when
the angle of the cam is reduced. If it is necessary to increase
the angle of the cam, you must first increase the angle of the
servomotor by means of the “output increase” key, then
increase the angle of cam III, and finally bring the
servomotor to the position of MIN output, with the “output
reduction” key. For any necessary adjustment of cam III,
especially for small movements, use the specific key 10).
Nm
3
/h
(max. burner delivery)
360
Summary of Contents for RS 200/M BLU
Page 2: ...Translation of the original instructions ...
Page 51: ...49 20152093 GB Appendix Electrical panel layout 0 ...
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