Gas Train; Gas Train Installation; Gas Pressure - Riello RLS 160/M MX Installation, Use And Maintenance Instructions

5.12.2 Gas train

Type-approved in accordance with EN 676 and supplied
separately from the burner.
To select the correct gas train model, refer to the manual "Burner-
gas train combination" supplied with the unit.

5.12.3 Gas train installation

Disconnect the power supply using the system
main switch.
DANGER
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.
• The gas train must be connected to the gas connection
1)(Fig. 32), using the flange 2), the gasket 3) and the screws
4) supplied with the burner.
• The train can enter the burner from the right or left side,
depending on which is the most convenient, see Fig. 32.
• The gas solenoids must be as close as possible to the burner
to ensure that the gas reaches the combustion head within
the safety time of 3s.
• Make sure that the pressure governor calibration range
(colour of the spring) includes the pressure required by the
burner.
20148049
Installation

5.12.4 Gas pressure

Tab. L indicates the pressure drops of the combustion head and
gas butterfly valve depending on the burner operating output.
The values shown in Tab. L refer to:
–
–
The adjacent table shows the minimum pressure drops along the
gas supply line depending on the maximum burner output.
Combustion head pressure drop.
Gas pressure measured at test point 1)(Fig. 33), with:
•
•
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)(Fig. 33).
Find in Tab. L the pressure value closest to the result of the
subtraction.
Read the corresponding output on the left.
Example with natural gas G20.
Operation at maximum modulating output: 1550 kW
Gas pressure at test point 1)(Fig. 33)
Pressure in combustion chamber
A pressure of 15.0 mbar corresponds in Tab. L to an output of
1550 kW.
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)(Fig. 33),
set the maximum output required from the burner operation:
Find in Tab. L the output value closest to the desired value.
Read, on the right, the pressure at test point 1)(Fig. 33).
Add this value to the estimated pressure in combustion chamber.
D3002
Fig. 32
26 GB
kW
G 20
930 5.2
1033 6.5
1137 8
1240 9.6
1343 11.3
1447 13.1
1550 15
1653 17
1757 19.2
1860 21.5
Data of head thermal power and gas pressure
refer to operation with gas butterfly valve fully
open (90°).
ATTENTION
Natural gas G 20 NCV 9.45 kWh/Sm
Natural gas G 25 NCV 8.13 kWh/Sm
combustion chamber at 0 mbar;
combustion head adjusted as in the diagram Fig. 22.
(mbar)
G 25 G 31
7.8 6.9
9.8 8.7
12 10.6
14.3 12.7
16.8 15
19.5 17.4
22.4 20
25.4 22.7
28.7 25.6
32.1 28.6
Tab. L
3 3
(8.2 Mcal/Sm )
3 3
(7.0 Mcal/Sm )
= 18.0 mbar
= 3.0 mbar
18.0 - 3.0 = 15.0 mbar