Riello 20190698, Инструкции по установке, использованию и обслуживанию

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20190798 22 GB
Installation
Column 1
Combustion head pressure drop.
Gas pressure measured at test point 1)(Fig. 25), with:
•
combustion chamber at 0 mbar
• burner working at maximum output
Column 2
Pressure drop at gas butterfly valve 2)(Fig. 25) with maximum
opening: 90°.
To calculate the approximate output at which the burner
operates:
–
subtract the combustion chamber pressure from the gas
pressure measured at test point 1)(Fig. 25).
– Find in Tab. G related to the burner concerned, the pressure
value closest to the result of the subtraction.
– Read the corresponding output on the left.
Example with G 20 natural gas:
Maximum output operation
Gas pressure at test point 1)(Fig. 25)
= 11.8 mbar
Pressure in combustion chamber = 3.0 mbar
11.8 - 3.0 = 8.8 mbar
A pressure of 8.8 mbar, column 1, corresponds in the table
Tab. G to an output of 1700 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. 25),
set the maximum modulating output required from the burner
operation:
–
find the nearest output value in Tab. G for the burner in
question.
– Read, on the right (column 1), the pressure at the test point
1)(Fig. 25).
– Add this value to the estimated pressure in combustion
chamber.
Example with G 20 natural gas:
Operating at the desired maximum output: 1700 kW
Gas pressure at an output of 1700 kW
= 8.8 mbar
Pressure in combustion chamber = 3.0 mbar
8.8 + 3.0 = 11.8 mbar
pressure required at test point 1)(Fig. 25).
1
2
Fig. 25
S8883