Combustion Head Setting; Modulation Minimum Output - Riello RS 28/E Installation, Use And Maintenance Instructions

4.8

Combustion head setting

Installation operations are now at the stage where the blast tube
and sleeve are secured to the boiler as shown in Fig. 12.
The fan part of the burner shall be completely back-
ward using the guides.
WARNING
AIR
Notches (Air = Gas)
Burner max output
Installation
4.8.1
When the MIN output is within the value range given in Tab. F, the
gas ring 2) (Fig. 12) is adjusted to zero.
GAS
There are two possible cases:
A
In diagram (Fig. 13), depending on the MAX output, find the notch
to use for adjusting the air and the gas.
Proceed as follows.
Air adjustment (Fig. 12)
 Turn screw 4) until the notch identified is aligned with the front
Gas adjustment (Fig. 12)
 Loosen screw 1) and turn ring 2) until the notch identified is
 Tighten the screw 1) fully down.
Example:
D2315
the burner RS 28/E varies its output between:
Fig. 12
MIN = 300 and MAX = 990 MBtu/hr.
The MIN output of 300 MBtu/hr is not found in the values of Tab. F
and therefore diagram (Fig. 13) is valid, from which it results that
for a MAX output of 990 MBtu/hr the gas and air adjustments are
done on notch 4, as in Fig. 12.
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In this case the pressure load loss of the combustion head is given
by column A Tab. G, page 19.
Diagram (Fig. 13) shows the ideal settings for the ring 2)(Fig. 12).
If the gas supply pressure is too low to reach the max output oper-
ation pressure indicated in Tab. G, and if the ring 2)(Fig. 12) is not
fully open, it can be opened wider by 1 or 2 notches.
Continuing with the previous example, Tab. G indicates that for
burner RS 28/E with output of 990 MBtu/hr a pressure of approxi-
mately 2.2" WC is necessary at test point 6)(Fig. 12).
If this pressure cannot be reached, open the ring 2)(Fig. 12) to
Fig. 13
notch 4 or 5.
Make sure that the combustion characteristics are satisfactory and
free of pulsations.
B
Air adjustment (Fig. 12)
 The same as the previous case: follow diagramm (Fig. 13).
Gas adjustment (Fig. 12)
 The gas ring 2)(Fig. 12) is always adjusted to position 0, irre-
 In this case the pressure load loss of the combustion heads is
17 GB

Modulation minimum output

Model
RS 28/E 198 - 280
RS 38/E 266 - 375
The MIN burner output is not in the values of Tab. F
surface 5) of the flange.
aligned with index 3).
The MIN burner output is found in the values of the Tab. F
spective of the MAX burner.
given by column B in Tab. G.
MBtu/hr kW
58 - 82
78 - 110
Tab. F
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