Bosch D340, Installation Manual

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Duct smoke housing, 2-wire Mounting | en 9
Bosch Security Systems, Inc. Installation manual 2017.04 | 7.0 | F.01U.071.685
1 Place tape over these sample holes
You can combine or cut sample tubes to make different lengths. A sample tube can be a
maximum length of 10 ft (3 m) or a minimum length of 1 ft (0.3 m). For example, you can join
a 3 ft (1 m) and a 5 ft (1.5 m) to make an 8 ft (2.4 m) sample tube.
Notice!
Sample tubes must have at least 12 sample holes within the duct. Do not cut a sample tube
to less than 12 sample holes.
Notice!
Sample tubes over 3 ft (1 m) must be supported at the end opposite the duct detector. The
support hole should be 1 in. to 2 in. (2.5 cm to 5 cm) below the entry hole to allow for
possible moisture drainage (see the figure following step 4 of the following procedure).
To combine sample tubes:
1.
Remove the roll pin and set screw from one of the sample tubes.
2. Remove the end plug from the other sample tube.
3. Push the flared end over the sample tube you want to lengthen.
4. Align the holes, insert the set screw, and reinstall the end plug. For example, if you want
a 7 ft (2 m) sample tube, combine a 3 ft (1 m) sample tube and a 5 ft (1.5 m) sample
tube. Then cut 1 ft (0.3 m) from the narrow end to get the necessary length.
Figure 3.5: Support hole position
1 1 in. to 2 in. (2.5 cm to 5 cm)
5. Seal the gap between duct and sample tube. You can remove up to 6 in. (15 cm) from the
D344‑1.5 for 1 ft (0.3 m) duct installations.
3.4 Mounting the detector
1. Locate the D340 mounting template and remove it from its backing. Place the template
over the desired location on the duct (see the following figure).