Alarko ALG 120/M, Installation Operation & Maintenance

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GAS LINE PRESSURE LOSS GRAPHS & CAPACITY ADJUSTMENT
The following graphs show the minimum “gas line inlet pressure” and “burner gas pressure” values
for burners having various gas line diameters and various gas line types. The measuring points of
these values are respectively shown in 3. and 12. points on page 9. “Combustion chamber pressure”
must be added to the values gathered from the graphs according to the capacity need. Combustion
chamber pressure can be measured on the boiler front door or via the measuring nipple placed on
the connection body of the boiler (see page 9). The “burner gas pressure” which is found with this
method is the gas pressure to achieve the desired capacity. “Gas line inlet pressure” should be
calculated to supply the desired burner gas pressure.
The graphs are given under standard conditions (15 °C and 1013 mbar). The ratio of densities of NG
to air is taken as 0,595. The graphs may change according to the gas supplied.
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Lower Heating Value of NG : 8250 kcal/m³
Lower Heating Value of mix LPG : 26000 kcal/m³
Burner Gas Pressure
Gas Line Inlet Pressure
ALG 200/M GAS LINE PRESSURE LOSS (Natural Gas)
Burner Gas Pressure
MBC 700 VEF Gas Line
(DN 50)
MBC 1200 VEF Gas Line
(DN 50)
MBC 1900 VEF Gas Line
(DN 65 )
MBC 3100 VEF Gas Line
(DN 80)
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
600 800 1000 1200 1400 1600 1800 2000 2200
CAPACITY (kW)
PR
ES
SU
R
E
L
O
SS
(m
b
a
r)