Riello 3897304, Installation, Use And Maintenance Instructions

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20098687
20 GB
Installation
5.10.2 Gas train
Approved according to standard EN 676 and provided separately
from the burner.
To select the correct gas train model, refer to the supplied “Burn-
er-gas train combination” manual.
5.10.3 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. 20.
The gas train must be connected to the gas connection
1)(Fig. 20), using the flange 2), the gasket 3) and the screws 4)
supplied with the burner.
See the accompanying instructions for the adjustment of the gas
train.
5.10.4 Gas pressure
Tab. H indicates the pressure drops of the combustion head and
gas butterfly valve, on the basis of the burner operating output.
Tab. H
The values shown in Tab. H refer to:
–
Natural gas G 20 NCV 9.45 kWh/Sm
3
(8.2 Mcal/Sm
3
)
– Natural gas G 25 NCV 8.13 kWh/Sm
3
(7.0 Mcal/Sm
3
)
Column 1
Combustion head pressure drop.
Gas pressure measured at test point 1)(Fig. 21), with:
•
combustion chamber at 0 mbar
• burner working at maximum output
Column 2
Pressure loss at gas butterfly valve 2)(Fig. 21) with maximum
opening: 90°.
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 1) (Fig. 21).
– Find, in Tab. H related to the burner concerned, the pressure
value closest to the result of the subtraction.
– Read off the corresponding output on the left.
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.
WARNING
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.
Ensure that the maximum pressure to the burner
is within the calibration range of the pressure ad-
juster.
kW
1
∆
p (mbar) 2
∆
p (mbar)
G 20 G 25 G 20 G 25
190 2.6 3.9 0.8 1.2
280 5.0 7.5 1.1 1.6
400 7.5 11.2 2.8 4.2
480 10.6 15.8 3.4 5.1
550 12.4 18.5 5.4 8.1
Fig. 20
D505