14 Intelligent Products—DH500 Series Intelligent Air Duct Smoke Detector
d h fig 3
Air Flow D irec tio n
S a m p le In let H o les
T ub e
E n d P lug
.....
Arrows sho u ld
fa c e in to
a ir flow .
Figure 5: Air Duct Detector Inlet Sampling Tube
Installation for Ducts less than Eight Feet Wide
1.
If the inlet tube is longer than the width of the air duct:
Drill a 3/4 inch hole in the duct directly opposite the hole already cut
for the inlet tube.
2.
If the inlet tube is shorter than the width of the air duct:
Install the end cap into the inlet tube (Figure 5).
3.
Slide the inlet tube into the bushing located in the center of the duct
detector housing.
4.
Position the tube so that the arrows point into the air flow.
5.
Secure the tube flange to the housing bushing with the two No. 6
self-tapping screws.
6.
For tubes longer than the width of the air duct, extend the tube out of
the opposite side of the duct.
7.
If there are more than two holes in the section of the tube extending
out of the duct, select a different tube length as described in
Table 4: Sampling Inlet Tubes in the Mounting, Mount Duct Housing
section of this technical bulletin.
8.
Otherwise, trim the end of the tube protruding through the duct so that
one to two inches of the tube extends outside the duct.
9.
Plug this end with the tube end plug, and tape close any holes in the
protruding section of the tube.
10. Seal the duct when the tube protrudes.
11. Support any inlet tube over three feet long on the opposite side of the
duct detector housing.