Servomotor Adjustment; Combustion Air Adjustment - Riello RLS 1000/M C13 Installation, Use And Maintenance Instructions

6.8

Servomotor adjustment

The servomotor (Fig. 33) adjusts simultaneously, through driving
gears, the output and pressure of the air and the delivery of the
fuel in use.
It is equipped with adjustable cams which operate as many
switches.
Cam I: limits the servomotor limit switch on the maxi-
mum position (about 130°) (light oil operation).
Cam II: limits the servomotor limit switch on the 0 posi-
tion°. With the burner off the air damper is com-
pletely closed (light oil and gas operation).
Cam III: regulates the minimum modulating output.
Position 45 is factory set (minimum light oil op-
eration).
Cam IV: limits the servomotor limit switch on the max
position (about 130°) (gas operation).
Cam V: regulates the minimum modulating output.
Factory set at position 45 (gas operation).
Rem. cams: not used
Lever 7: servomotor reset
6.9

Combustion air adjustment

The fuel/combustion synchronization is made by means of a ser-
vomotor connected to two variable profile cams, which act on the
outlet air damper 1)(Fig. 34) and gas damper 2) and on the com-
bustion head by appropriate levers.
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, fuel step according to the burner out-
put required, with servomotor completely open, is carried out by
the pressure stabiliser placed on the train.
D11563
2
Start-up, calibration and operation of the burner
1
S8446
The values indicated in Tab. K and Tab. L can be a reference for
a good combustion calibration.
EN 676
Theoretical
max. CO
GAS
0 % O
G 20 11.7
G 25 11.5
G 30 14.0
G 31 13.7
EN 267
Theoretical max. CO
0 % O
2
15.2
Fig. 34
31 GB
7
Air excess
Max. output Max. output
  1.2   1.3
CO % Calibration
2
2
 = 1.3
 = 1.2
2
9.7
9.5
11.6 10.7
11.4 10.5
Air excess
Max. output Min. output
  1.2   1.3
CO % Calibration
2
2
 = 1.2  = 1.3
12.6
Fig. 33
CO
mg/kWh
 1000
9
 1000
8.8
 1000
 1000
Tab. K
CO
mg/kWh
 1000
11.5
Tab. L
20040160