Air / Fuel Adjustment; Air Adjustment For Maximum Output; Air/Fuel Adjustment And Output Modulation System; Burner Adjustment - Riello RLS 810/E FGR Installation, Use And Maintenance Instructions

6.8

Air / fuel adjustment

Air/fuel synchronisation is carried out with the relevant air and
gas servomotors by logging a calibration curve by using the elec-
tronic cam.
It is advisable, to reduce the loss and for a wide calibration field,
to adjust the servomotors to the maximum of the output used, the
nearest possible to the maximum opening (90°).
The choking of the air, taking into account the maximum combus-
tion output, takes place by varying the adjustment of the combus-
tion head (see "Combustion head adjustment" on page 22).
On the gas butterfly valve 29)(Fig. 4 on page 11), the fuel step
according to the burner output required, with servomotor com-
pletely open, is carried out by the pressure stabiliser on the gas
train.
6.8.1

Air adjustment for maximum output

 Adjust the servomotor to maximum opening (nearly 90°) so
that the air butterfly valves are entirely open.
6.8.2 Air/fuel adjustment and output modulation
system
The air/gas regulator and output modulation system equipping
RS/E series burners performs a number of integrated functions to
optimise burner function, in both individual installations and in
combination with other units (e.g. double furnace boiler or multi-
ple heat generators in parallel).
The basic system functions control:
1 The dosage of the air and fuel through positioning using
direct servocommands of the relevant valves eliminating the
possible play in the calibration systems with mechanical
cam lever mechanisms, used on traditional modulating
burners.
2 The modulation of the burner output in accordance with the
load required by the system, with maintenance of the pres-
sure or temperature of the boiler at the operating values set.
3 The sequence (cascade adjustment) of more than one
boiler through the suitable connection of the various units
and the activation of the internal software of the individual
systems (option).
Further interfaces and communication functions with computers,
for remote control or integration in central supervision systems
are available on the basis of the configuration of the system.
The first start up and every further internal setting
operation of the adjustment system or the expan-
sion of the base functions require access by
means of password and are to be carried out by
WARNING
service personnel who are especially trained for
the internal programming of the instrument and
the specific application created with this burner.
Start-up, calibration and operation of the burner
6.8.3

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
6.8.4 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 5400 kW.
Ignition output must be equal to or lower than:
1800 kW with ts = 3 s.
In order to measure the ignition output:
 disconnect the plug-socket on the flame sensor (the burner
starts up and then goes into lockout after the safety time has
elapsed).
 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:
Sm
Example for G 20 gas (9.45 kWh/Sm
Max. operation output: 5400 kW corresponding to 571.4 Sm
After 10 ignitions with their lockouts, the delivery indicated on the
meter must be equal to or less than: 571.4 : 360 = 1.58 Sm
Air adjustment
The air is adjusted by varying the angle of the air
damper 41)(Fig. 4 on page 11) by changing the air servomotor
degrees inside the programme of the electronic cam.
6.8.5

Maximum output

The MAX output must be set within the firing rate indicated in
Fig. 2 on page 10.
Adjustment of gas delivery
Measure the gas delivery on the gas meter.
A rough indication can be obtained from on page 29, just read
the gas pressure on the "U" pressure gauge (see Fig. 31 on
page 32) 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.
33 GB
3 /h (max. burner delivery)
360
3
):
3
/h.
3
20171988