Miele PDR 910 G Installationsplan Seite 39

Procedure
Sample calculation
Adding together the relative pipe lengths for all of the components
gives the total ducting length. The total ducting length expresses the
resistance of the entire exhaust air system.
As a larger duct diameter has a lower flow resistance, a longer duct
requires a greater duct diameter (table II).
1. Measure the length needed for the straight sections of ducting.
Multiply this value by the corresponding relative pipe length
from table I.
2. Calculate the number of bends and components needed. Use
Table I to help you add together their relative pipe lengths.
3. Add together all of the relative pipe lengths calculated above in
order to calculate the total ducting length.
4. Refer to Table II for the pipe diameter needed for the total duct-
ing length.
Table I
Components
Exhaust air hose (flexible aluminium)* / pipe
(temperature resistance min. 80 °C)
– 1 m laid straight or 1 m straight pipe
– 45° bend (radius of bend = 0.25 m)
– 90° bend (radius of bend = 0.25 m)
Non-return flap*
* optional accessories
Table II
Maximum permissible total duct-
ing length
20 m
40 m
80 m
en - Installation notes
Relative pipe
length
1.0 m
0.6 m
0.8 m
14.3 m
Required diameter
100 mm
125 mm
150 mm
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