Bosch FAD-420-HS-EN Duct Smoke Detector - Manual (Page 60)

60 en | Installation Duct Smoke Detector
F.01U.033.733 | 5.0 | 2011.11 Installation guide Bosch Sicherheitssysteme GmbH
2. Place drilling jig in the selected installation location on the
ventilation duct and stick it down (see Figure 4.5).
3. Drill two
∅ 9.5-mm holes in the ventilation duct for the two
expanding nuts to secure the housing, and drill the
∅ 44.5-
mm openings for the sample tube and ventilation tube.
4. Remove the drilling jig, deburr sharp edges, and remove
debris and dirt.
5. Place expanding nuts #10-24 (see Figure 4.6) in the two
∅ 9.5-mm holes.
6. Screw the #10-24 x 1 in. screws into the expanding nuts
and tighten by hand. This ensures the expanding nuts are
fixed securely in the ventilation duct.
The expanding nuts can be held securely with a pair of
pliers to stop them turning as the screws are screwed in.
7. Now remove both screws.
Figure 4.6 Expanding nuts #10-24
Figure 4.4 Drilling jig
No. Description
a
∅ 44.5-mm holes for sample
tube and ventilation tube
b
∅ 9.5-mm holes for securing
housing
Figure 4.5 Position of the drilling jig
No. Description
c Ventilation duct
d Drilling jig