Unigas K750A, Руководство пользователя

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PART I: SPECIFICATIONS
10
“MAX” position (see paragraph “Adjusting the combustion head”); the minimum output point is reached setting the combustion head to its “MIN” position.
During the first ignition, the combustion head is set in order to find a compromise between the burner output and the generator specifications, that is why
the minimum output may be different from the Performance curve minimum
Pressure in the Network / gas flow rate curves(natural gas)
Combustion head gas pressure curves
Combustion head gas pressure depends on gas flow and combustion chamber backpressure. When backpressure is subtracted, it
depends only on gas flow, provided combustion is properly adjusted, flue gases residual O2 percentage complies with “Recommended
combustion values” table and CO in the standard limits). During this stage, the combustion head, the gas butterfly valve and the
actuator are at the maximum opening. Refer to , showing the correct way to measure the gas pressure, considering the values of
pressure in combustion chamber, surveyed by means of the pressure gauge or taken from the boiler’s Technical specifications.
.
G
AS PRESSURE IN
TH
E NETW
O
R
K mbar
K750A M-
Gas rate Stm
3
/h
G
AS PRESSURE IN
TH
E NETW
O
R
K
mbar
K890A M-
Gas rate Stm
3
/h
K990A M-
Gas rate Stm
3
/h
WARNING: the diagrams refers to natural gas. For different type of fuel please refer to the paragraph “Fuel” at
the beginning of this chapter.
The values in the diagrams refer to natural gas with a calorific value of 8125 kcal/Stm
3
(15°C, 1013 mbar) and a density of
0.714 kg/Stm
3
.
The values in the diagrams refer to GPL with a calorific value of 22300 kcal/Stm
3
(15°C, 1013 mbar) and a density of 2.14 kg/
Stm
3
. When the calorific value and the density change, the pressure values should be adjusted accordingly.
Where:
Natural gas pressure shown in diagram
Real gas pressure
Natural gas flow rate shown in diagram
Real gas flow rate
Natural gas density shown in diagram
Real gas density