(A)
(B)
D9412
D454
pressur
e in comb
ustion
cha
m
ber
mb
ar
length of combustion
chamber
m
4
FIRING RATES (A)
The burner delivery must be selected within area
of the adjacent diagram.
This area is called firing rate and provides the
delivery of the burner in relation to the pressure
in the combustion chamber.
The work point may be found by plotting a verti-
cal line from the desired delivery and a horizontal
line from the pressure in the combustion cham-
ber. The intersection of these two lines is the
work point which must lie within firing rate.
Important:
the FIRING RATE area values have been ob-
tained considering a surrounding temperature
of 20 °C, and an atmospheric pressure of 1013
mbar (approx. 0 m above sea level) and with
the combustion head adjusted as shown on
page 7.
TEST BOILER (B)
The firing rate was set in relation to special test
boilers in accordance with the methods defined
in EN 267 standards.
Figure (B) indicates the diameter and length of
the test combustion chamber.
Example:
Delivery 35 kg/hour:
diameter = 50 cm; length = 1.5 m.
Whenever the burner is operated in a much
smaller
commercially-available
combustion
chamber, a preliminary test should be per-
formed.
