Riello GAS Series - Gas Train; Gas Train Installation; Gas Pressure

2915858
18
GB
Installation
5.8.2 Gas train
Approved according to standard EN 676 and provided separately
from the burner.
5.8.3 Gas train installation
The train can enter the burner from the right or left side, depend-
ing on which is the most convenient, see Fig. 5.
5.8.4 Gas pressure
Tab. F indicates the pressure drops of the combustion head and
gas butterfly valve, on the basis of the burner operating output.
Tab. F
The values shown in Tab. F on page 18 refer to:
- Natural gas G 20 NCV 10 kWh/Sm
3
(8.6 Mcal/Sm
3
)
- Natural gas G 25 NCV 8.6 kWh/Sm
3
(7.4 Mcal/Sm
3
)
Column 1
Combustion head pressure drop.
Gas pressure measured at test point 12)(Fig. 5 on page 11), with:
- combustion chamber at 0 mbar;
- Gas G20 (methane)
To calculate the approximate output at which the burner oper-
ates:
- subtract the pressure in combustion chamber from the gas
pressure measured at test point 12)(Fig. 5 on page 11).
- Find in Tab. F related to the burner concerned, the pressure
value closest to the result of the subtraction.
- Read the corresponding output on the left.
Example GAS 3 with natural gas G20:
Pressure of the gas at the socket = 10.3 mbar
Pressure in combustion chamber = 2 mbar
10.3 - 2 = 8.3 mbar
A pressure of 5.3 mbar, column 1, corresponds in Tab. F to an
output of 277 kW.
This value serves as a rough guide; the effective output must be
measured at the gas meter.
To find out
on the other hand the gas pressure required at the
socket 12)(Fig. 5 on page 11), having fixed the output at which
you want the burner to operate:
- find the nearest output value in Tab. F for the burner in ques-
tion.
- Read on the right, column 1, the pressure at the test point
12)(Fig. 5 on page 11).
- Add this value to the estimated pressure in combustion
chamber.
Example GAS 3 with natural gas G20:
Desired output: 277 kW
Gas pressure at an output of 277 kW = 8.3 mbar
Pressure in combustion chamber = 2 mbar
8.3 + 2 = 10.3 mbar
pressure required at test point 12)(Fig. 5 on page 11).
DANGER
Disconnect the electrical power using the main
switch.
Check that there are no gas leaks.
Pay attention when handling the train: danger of
crushing of limbs.
Make sure that the gas train is properly installed
by checking for any fuel leaks.
The operator must use the required equipment
during installation.
kW
1 p (mbar)
G20 G25
130 3.6 5,3
154 4.1 6.1
179 4.8 7.1
203 5.5 8.1
228 6.3 9.4
252 7.2 10.8
277 8.3 12.3
301 9.4 13.9
326 10.6 15.8
350 11.9 17.7
WARNING
The heat output and gas pressure in the head
data refer to operating with the gas butterfly
valve fully open (90°).
Fig. 19
S9708