Element4 POWERFAN MKII, Инструкция по установке и эксплуатации, Страница: 16 / 24

INSTALLATIEHANDLEIDING
17
3.4 Extra resistance in the channel
As with a regular, non-mechanical flue situation, adding bends
in the flue configuration of the PowerFan also provides extra
resistance. These bends must be taken into account by counting
them as an extra flue length.
There are two types of bends that may occur in a flue situation.
•
N
-bends
Curves from the vertical plane to the horizontal plane
or
Curves from the horizontal to the vertical.
•
Q
-bends
Curves in the horizontal plane
With these two bends, there are three situations that can offer
extra resistance to your flue ( Figure 3.14 ).
•
Q
-bends (both
90°
and
45°
) are calculated as a 0.5 meter
discharge length.
• Positive
N
-bends (both
90°
and
45°
) are calculated as a 0.25
meter discharge length.
After a negative
N
-bend, that is, an
N
-bend after which the flue
goes down vertically (
N
-
), the entire discharge length must be
counted twice until it bends again to the horizontal plane or
rises again. ( Figure 3.15 .)
So for
C
2
, every meter counts for 2 meters.
The calculated extra resistance of the bends applies to all
superstructure systems.
X
Y
Z
X
Y
Z
X
Y
Z
X
Y
Z
X
Y
Z
Q
90°
Q
45°
N
+
90°
N
+
45°
N
-
90°
N
-
45°
X
Y
Z
Figure 3.14 - Bend directions for extra resistance calculation
B
1
A
C
2
B
2
C
1
Figure 3.15 - Example setup of negative vertical flue