Viessmann H32E, Инструкция по установке и обслуживанию, Страница: 56 / 80

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1. Measure the pressure using the pressure differen-
tial measuring device. For this, connect the meas-
uring hoses with the connectors. Measure the
pressure. Read the setting in the pressure drop
diagram.
2. Adjust the setting on the aperture scale.
3. Save the setting: Tighten the screws on the adjust-
ment mechanism.
10
Pressure drop in Pa
50
36 180
Flow rate in m³/h
300
200
100
1 2
3
4
216 144 108 72
Fig. 79 Pressure drop graph, iris diaphragm DN 125
Iris diaphragm DN 125
Value from graph
Setting, iris diaphragm
1.0 1.9
1.5 2.4
2.0 3.1
2.5 3.8
3.0 4.8
3.5 6.1
4.0 7.9
4.5 10.7
Example:
Setting iris diaphragm DN 160
■ Measured pressure drop: 30 Pa
■
Required air flow rate: 180 m 3 /h
■
Value calculated from diagram: 3.0
■
Read K value to adjust the scale from table: 8.9
5
Pressure drop in Pa
30
72 324
Flow rate in m³/h
200
100
180
10
1 2
3
4
5
108 144 252
Fig. 80 Pressure drop graph, iris diaphragm DN 160
Iris diaphragm DN 160
Value from graph
Setting, iris diaphragm
1.0 4.1
1.5 4.9
2.0 6.1
2.5 7.4
3.0 8.9
3.5 11
4.0 13.6
4.5 17.9
5.0 25.4
Measuring with impeller air speed meter, iris diaphragm
■
Measure the air speed with the impeller air speed
meter (or the air flow rate directly). Observe the
instructions of the test equipment manufacturer.
■
Adjust the air flow rate in accordance with the devia-
tion.
■
Secure the vent in position.
Note
Adjusting air flow rates with the use of an impeller air
speed meter will
not provide high accuracy. Deviations
of
±
10 % are possible.
Presetting supply air and extract air apertures
You will need the following engineering details:
■
Pressure drop for the individual sections
■
Air flow rates for the individual sections
Using these details, the required aperture width for the
supply air and extract air apertures can be obtained
from the relevant diagrams.
Commissioning, inspection, maintenance
Presetting the air flow rate
(cont.)
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