17
Important
Damage to the bearings or other parts of the fan
can occur.
♦
Do not place a duct bend directly before or
after the fan!
♦
Ensure a smooth and constant air flow to the
device.
Ø
D
min.
2,5x Ø
D
min.
2,5x Ø
D
• Round duct system:
D
= Nominal diameter
• Rectangular duct system:
D
= Hydraulic diameter
Air gap
For all work on the fan care should be taken that the gap between the fan impeller and the fixed housing components
is regular. The minimum distances must be at least 1 % of the greatest contact diameter, but no less than 2 mm. For
double inlet fans the gap must be checked on both inlet sides.
Ensure that the air gap between the housing and the impeller is complied with.
You can find precise information on the minimum air gap of the fans in this chapter.
♦
Check if the air gap complies with these data.
♦
Do not install the fan if the gap is not complied with
the mentioned data.
Below sketch illustrates the different kinds of
air gaps
.
Radial fan
Axial fan
X
X
X
8.1
Installation AW-EX, AXC-EX, AXCBF-EX
Air gap
Table 11 Air gap AW-EX
Nominal diameter
Min. air gap [mm]
Nominal diameter
Min. air gap [mm]
355
3.5
550
5.5
420
4.2
650
6.45
Table 12 Air gap AXC-EX, AXCBF-EX
Nominal diameter
Min. air gap [mm]
Nominal diameter
Min. air gap [mm]
250
2.5
800
5.0
315
2.5
900
7.0
355, 400
3.0
1000
7.0
450, 500
3.5
1120
8.0
560
3.5
1250
8.0
630
4.5
1400
10.0
710
5.0
1600
10.0
| 002
