Riello RLS 310/M MX, Регулируемая работа

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20084880 34 GB
Start-up, calibration and operation of the burner
6.10 Proceed with the calibration (gas)
The fuel/combustion synchronisation is done by means of a ser-
vomotor connected to two variable profile cams, which act on the
air dampers 1)(Fig. 34) and gas dampers 2)(Fig. 34).
It is advisable, to reduce the loss and for a wide calibration field,
to adjust the servomotor to the maximum of the output used, the
nearest possible to the maximum opening (130°).
On the gas butterfly valve, the choking of the fuel according to the
required output, is carried out using the cam 2)(Fig. 34).
The values in the table can be useful as reference for good fuel
calibration.
6.10.1 Burner adjustment
The optimum adjustment of the burner requires an analysis of
flue gases at the boiler outlet.
Adjust in sequence:
1 - Output upon ignition
2 - MAX output
3 - MIN output
4 - Intermediate outputs between Min. and Max.
5 - Air pressure switch
6 - Maximum gas pressure switch
7 - Minimum gas pressure switch
6.10.2 Output upon ignition
Ignition must occur at a lower output than the max. operation out-
put. Regulations provide that the ignition output of this burner
must be equal to or less than 1/3 of the MAX operation output.
Example: MAX operation output of 600 kW.
Ignition output must be equal to or lower than:
200 kW with ts = 3 s.
In order to measure the ignition output:

Obscure the flame sensor (the burner starts and goes into
lockout after the safety time).

Perform 10 ignitions with consecutive lockouts.

Read the quantity of gas burned on the meter.

This quantity must be equal to or lower than the quantity
given by the formula:
Example for G 20 gas (9.45 kWh/Sm
3
):
Max. operation output: 600 kW corresponding to 63.5 Sm
3
/h.
After 10 ignitions with their lockouts, the delivery indicated on the
meter must be equal to or less than: 63.5 : 360 = 0.176 Sm
3
Air adjustment
The air adjustment has already been carried out on the basis of
the light oil side calibration.
There could be variations to correct the gas combustion but this
involves a further check of the light oil operation.
6.10.3 Maximum output
The MAX output must be set within the firing rate indicated in
Fig. 3 on page 12.
In the above instructions we left the burner running at the MIN
output. Now press the “increase output” button 2)(Fig. 30 on
page 30), 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 gas meter.
A rough indication can be obtained from Tab. M on page 27, just
read the gas pressure on the “U” pressure gauge (see Fig. 33 on
page 33) and follow the indications.

If delivery needs to be reduced, diminish outlet gas pres-
sure; if it is already very low, slightly close the VR adjustment
valve.

If delivery needs to be increased, increase the adjuster out-
let gas pressure.

Screw or unscrew the screw 2) of the mechanical cam
(Fig. 34 on page 34) to increase or decrease the gas output
so as to adjust it to the corresponding air output, to obtain
optimal combustion.

Proceed in the same way with the other screws.
Key (Fig. 34)
1
Air adjustment cam
2 Gas adjustment cam
EN 676
Air excess
Max. output.
 
1.2
Min. output
 
1.3
GAS
Theoretical max
CO
2
0 % O
2
CO
2
% Calibration
CO
mg/kWh

= 1.2

= 1.3
G 20 11.7 9.7 9.0

100
G 25 11.5 9.5 8.8

100
G 30 14.0 11.6 10.7

100
G 31 13.7 11.4 10.5

100
EN 267
Air excess
Max. output.
 
1.2
Min. output
 
1.3
Theoretical max CO
2
0 % O
2
CO
2
% Calibration
CO
mg/kWh

= 1.2

= 1.3
15.2 12.6 11.5

100
Sm
3
/h
(max. burner delivery)
360
Fig. 34
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