RS 25/M BLU
1 p
(mbar)
kW
G20
125
1.8
140
2.6
160
3.8
180
4.9
200
6.0
220
7.2
240
8.3
260
9.4
280
10.5
300
11.7
320
12.8
340
13.9
360
15.0
370
15.6
(A)
(B)
RS 35/M BLU
2 p
(mbar)
kW
G20
0.1
200
0.1
220
0.1
240
0.2
260
0.2
280
0.2
300
0.3
320
0.3
340
0.4
360
0.5
380
0.5
400
0.6
420
0.7
440
0.7
460
480
1
2
1 p
2 p
(mbar)
(mbar)
G20
G20
2.8
0.2
3.6
0.2
4.4
0.3
5.2
0.3
6.0
0.4
6.8
0.4
7.6
0.5
8.5
0.6
9.3
0.6
10.1
0.7
10.9
0.8
11.7
0.8
12.5
0.9
13.3
1.0
14.1
1.1
S8738
6
GAS PRESSURE
The adjacent tables show minimum pressure
losses along the gas supply line depending on
the maximum burner output operation.
Column 1
Pressure loss at combustion head.
Pressure of the gas at the socket 1)(B), with
combustion chamber at 0 mbar.
Column 2
Pressure loss at gas butterfly valve 2)(B) with
maximum opening: 90°.
The values shown in the various tables refer to:
natural gas G 20 PCI 9.45 kWh/Sm
3
(8.2 Mcal/Sm
)
Calculate the approximate maximum output of
the burner in this way:
- subtract the combustion chamber pressure
from the gas pressure measured at test
point 1)(B).
- find, in the table relating to the burner con-
cerned, the pressure value closest to the
result of the subtraction.
- read the corresponding output on the left.
Example - RS 35/M BLU:
• Maximum output operation
• Natural gas G 20 PCI 9.45 kWh/Sm
• Gas pressure at test point 1)(B) =
• Pressure in combustion chamber =
11.3 - 2 = 9.3 mbar
A maximum output of 360 kW shown in Table
RS 35/M corresponds to 9.3 mbar pressure,
column 1.
This value serves as a rough guide; the effective
output must be measured at the gas meter.
To calculate the required gas pressure at test
point 1)(B), set the maximum output required
from the burner operation:
- find the nearest output value in the table for
the burner in question.
- read, on the right (column 1) the socket pres-
sure 1)(B).
- add this value to the estimated pressure in
the combustion chamber.
Example - RS 35/M BLU:
• Required burner maximum output operation:
360 kW
• Natural gas G 20 PCI 9.45 kWh/Sm
• Gas pressure at burner output of 360 kW,
taken from table RS 35/M BLU,
column 1
• Pressure in combustion chamber =
9.3 + 2 = 11.3 mbar
pressure required at test point 1)(B).
The
heat
output
pressure in the head data refer
to
operating
butterfly valve fully open (90°).
WARNING
3
3
11.3 mbar
2 mbar
3
=
9.3 mbar
2 mbar
and
gas
with
the
gas