Bosch D340, Installation Manual

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8 en | Mounting Duct smoke housing, 2-wire
2017.04 | 7.0 | F.01U.071.685 Installation manual Bosch Security Systems, Inc.
Figure 3.2: Mounting positions
1 Air flow 2 Acceptable mounting positions
3 Unacceptable mounting positions
3.3 Preparing sample tubes
The sample tubes must extend across the width of the duct. The three sizes of sample tubes
are:
–
D344-1.5 (1.5 ft [0.46 m])
– D344-3 (3 ft [0.91 m])
– D344-5 (5 ft [1.52 m])
Sample tubes include an end plug that must be installed in the narrow end of the tube (see
the following figure).
Figure 3.3: Sample tube
1 Set screw 2 End plug
When using the D344‑1.5 in installations where the duct width is between 12 in. (31 cm) and
18 in. (46 cm), cover some of the sample holes. The D344‑1.5 has 19 sample holes, but only
12 are required for normal installations. Depending on the length, you might have to cover
some of the holes with duct tape. Use even spacing when covering the sample holes to allow
an even sample across the width of the duct (see the following figure).
Figure 3.4: Covering sample tube holes