Combustion Head Setting - Riello RS 190/M Installation, Use And Maintenance Instructions

Installation
4.6

Combustion head setting

Installation operations are now at the stage where the blast tube
AIR GAS
and sleeve are secured to the boiler as shown in Fig. 9 and Fig. 10.
It is now a very simple matter to set up the combustion head, as this
depends solely on the MAX output developed by the burner.
It is therefore essential to establish this value before proceeding to
set up the combustion head.
There are two adjustments to make on the head:
air and gas deliveries.
In diagram (Fig. 11) find the notch to use for adjusting the air and
the gas.
Air adjustment
Turn screw 4)(Fig. 9) until the notch identified is aligned with the
front surface 5) of the flange.
D2399
Gas adjustment
Fig. 9
When the burner is installed for a maximum output  5726 MBtu/hr
unscrew and remove the front part 1)(Fig. 10). Replace it with the
S10060
supplied cap 2), after removing the inner pipe 3). Replace the disc
4) with the supplied disc without hole. If there is low gas supply
pressure, the head may be left in standard configuration, limiting
the minimum modulation to 1980 MBtu/hr.
GAS
Loosen the 3 screws 1)(Fig. 9) and turn ring 2) until the notch iden-
tified is aligned with index 3).
Tighten the 3 screws 1) fully down.
Example:
MAX output = 6000 MBtu/hr
If we consult diagram (Fig. 11) we find that for this output, air must
be adjusted using notch 3 (Fig. 9).
NOTE
Diagram (Fig. 11) shows the ideal settings for the ring 2)(Fig. 9).
If the gas main pressure is too low to reach the maximum output
operation pressure indicated on page 20, and if the ring 2)(Fig. 9)
Fig. 10
is not fully open, it can be opened wider by 1 or 2 notches.
Notches (Air = Gas)
Continuing with the previous example, page 20 indicates that with
D10512
output of 6000 MBtu/hr a pressure of approximately 3.15 "WC is
necessary at test point 6)(Fig. 9).
If the pressure cannot be reached, open the ring 2)(Fig. 9) to notch
4 or 5.
Maximum burner output
Fig. 11
16 GB
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