Firing Rates; Test Boiler - Riello RL 70/M Installation, Use And Maintenance Instructions

5.5

Firing rates

During operation, burner output varies between:
 MINIMUM OUTPUT: area A;
 MAXIMUM OUTPUT: area B (and C for model RL 130/M).
Graphs (Fig. 2):
Horizontal axis : Burner output
Vertical axis : Combustion chamber pressure
The work point may be found by plotting a vertical line from the
desired delivery and a horizontal line from the pressure in the
combustion chamber. The intersection of these two lines is the
work point which must lie within area A, for MIN output, and within
area B, for MAX output.
In order to utilize also area C (RL 130/M) it is necessary to per-
form the calibration of the combustion head as explained on
page 16.
The FIRING RATE area values have been ob-
tained considering a surrounding temperature of
20 °C, and an atmospheric pressure of 1000 mbar
(approx. 100 m above sea level) and with the
WARNING
combustion head adjusted as shown on page 18.
5.6

Test boiler

The burner/boiler combination does not pose any problems if the
boiler is EC approved and its combustion chamber dimensions
are similar to those indicated in the diagram (Fig. 3).
If the burner must be combined with a boiler that has not been EC
approved and/or its combustion chamber dimensions are clearly
smaller than those indicated in the diagram, consult the
manufacturer.
The firing rates were obtained in special test boilers, according to
EN 676 regulations.
Technical description of the burner
9 GB
In Fig. 3 you can see the diameter and length of the test
combustion chamber.
Example:
Output 650 Mcal/h (407 kW): diameter 60 cm - length 2 m.
MODULATING RATIO
The modulating ratio, obtained in test boilers, according to
standard (EN 267 for light oil), is of 4:1 for light oil.
D1218
Fig. 2
D497
Fig. 3
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