Combustion Air Adjustment; Air Adjustment For Maximum Output; Air/Fuel Control And Power Modulation System; General Information - Riello RS 300/E LN Installation, Use And Maintenance Instructions

5.5

Combustion air adjustment

Fuel/combustion air must be synchronized with the relevant ser-
vomotors (air and gas) by storing a setting curve by means of
the electronic cam.
To reduce pressure loss and to have a wider adjustment range,
it is best to set the servomotor to the maximum output used, as
near to maximum opening (90°) as possible.
On the gas butterfly valve, the fuel's partial setting adjustment
based on required output, with the servomotor fully open, is
made by using the pressure stabilizer on the gas train.
5.5.1

Air adjustment for maximum output

Set the servomotor to maximum opening (near 90°) so that the
air butterfly valves are fully open.
Loosen screw 2) (Fig. 38) under the burner's intake and close
grille 1) (Fig. 38) progressively until you achieve the required
output.
D3094
Fig. 38
The only time reducing intake to a partial setting is not neces-
sary is when the burner is working at the top of the operating
range given in Fig. 17.
We recommend you achieve the maximum output
required manually, and adjust intake to the partial
setting, define gas pressure and adjust the com-
WARNING
bustion head before completing the setting and
storing the fuel/combustion air synchronization
curves.
20008423
Start-up, calibration and operation of the burner
30
5.6

Air/fuel control and power modulation system

5.6.1

General information

The air/fuel and power modulation system installed on RS burn-
er series provides, a set of integrated functions ensuring top lev-
el energy and operational performance from the burner, both for
single and grouped burners (e.g. boiler with a double combus-
tion chamber or several generators in parallel).
The system includes the following basic functions:
 air and fuels are supplied in correct quantities by positioning
the valves by direct servo-control, thus avoiding the possibility
of play typical of systems used for traditional modulating burn-
ers, in which settings are obtained by levers and a mechani-
cal cam;
 burner power is modulated according to the load required by
the system, while boiler pressure or temperature is main-
tained at set operating values;
 a sequence (cascade control) of several boilers by suitably
connecting different units, and activation of internal software
in the individual systems (optional item).
Further interfaces and computer communication functions for
remote control or integration in centrally supervised systems are
available according to the system's configuration.
NOTE
The first start-up and all further operations concerning internal
settings of the control system or expansion of basic functions,
are accessed with a password and are reserved for technical
service personnel specifically trained for internal programming
of the instrument and for the specific application obtained with
this burner.
The first start-up and curve synchronization manual is supplied
with the burner.
The complete manual for checking and setting all parameters
will be provided on application.
GB