Item Description
1. Damper frame
2. Duct outlet
3. Fan (not limited to centrifugal)
4. 3/8 in. (10mm) minimum diameter bolts
5. Actuator
The actuators are to be installed to function per system
requirements and to be controlled by smoke detection
devices.
FAN ISOLATION APPLICATION
For air handling equipment isolation, leakage rated
dampers are designed to operate with blades running
horizontally. Dampers can be installed in a vertical
or horizontal position. Sealants and damper seal
materials meet the requirements of NFPA90A for smoke
developed rating (<50) and flame spread index (<25) as
tested per UL723/ASTME84-91A/NFPA 255. Dampers
can be attached to the fan system discharge or inlet
without being 24 in. (610mm) of a smoke barrier when
used as an air handling equipment isolation damper.
4
1
2
3
Size Limitations
* All multiple section assemblies are factory assembled.
5
in inches
(mm)
Maximum single
section size
Maximum single
section size when
multi-section
assembly
Maximum overall
multi-section size*
HSD-401 60 x 60
(1524 x 1524)
48 x 60
(1219 x 1524)
120 x 60
(3048 x 1524) or
48 x 120
(1219 x 3048)
1. SMOKE DAMPER REQUIREMENTS AND
APPLICATION
Smoke dampers are required to close and prevent the
passage of air and smoke through ducts or ventilation
openings in smoke barriers. Smoke dampers are also
applied in engineered smoke control systems to establish
air pressure differentials and thereby prevent the spread
of smoke. HSD-401 damper is designed to operate with
blades running horizontally. Dampers can be vertically or
horizontally installed at, in accordance with NFPA-90A,
or adjacent to the point where the duct passes thru the
smoke barrier.
2. LOCATION OF DAMPER IN DUCTWORK
Place the damper assembly in its proper position relative
to the barrier. The plane of the closed damper blades
must be within 24 in. (610mm) of the rated smoke barrier
and before any duct inlets or outlets.
3. ATTACHING DAMPER TO THE DUCT
HSD-401 damper is a flange mounted to the duct, sleeve,
or wall opening with 3/8 in. (10mm) minimum diameter
bolts and spaced a maximum of 6 in. (152mm) apart, on
center. Dampers can be attached directly to the fan, if
required.
4. SEALING THE INSTALLATION
After installing the damper in the ductwork, seal the
joint between the damper frame and the duct using Dow
Corning RTV 732 Sealant. Make sure to press the sealant
into the joint to guarantee a proper seal. Use the minimum
amount of material required to completely seal the joint.
5. ACTUATOR CONNECTIONS
Electrical and/or pneumatic connections to damper
actuators should be made in accordance with wiring and
piping diagrams developed in compliance with applicable
codes, ordinances and regulations.
