Application
Model SMD-301 is a leakage rated smoke damper with extremely
low leakage. The SMD-301 serves the function of both a control
damper and smoke damper. High strength airfoil blades insure
lowest resistance to airflow in HVAC systems with velocities to
3000 fpm (15.2m/s) and 4 in. wg (1.0 kPa) Model SMD-301 may be
installed vertically (with blades running horizontal) or horizontally
and is rated for airflow and leakage in either direction.
UL555S Leakage Rating
Leakage Class: I
Operational Rating
Maximum Velocity: 3000 fpm (15.2 m/s)
Maximum Pressure: 4 in. wg (1 kPa)
Maximum Temperature: 350ºF (177ºC) depending on
actuator
Standard Construction
Frame: 5 in. x 1 in. (127mm x 25mm)
galvanized steel hat channel with
reinforced corners. A low profile
head and sill are used on sizes less
than 17 in. (432mm) high to
maximize free area and
performance.
Blades: Double skin airfoil shape of
galvanized steel with full length
structural reinforcement. 14 ga.
(2 mm) equivalent thickness.
Seals: Extruded silicone rubber blade
seals. Flexible stainless steel jamb
seals.
Linkage: Concealed in jamb.
Axles:
Bearings: Bronze sleeve type.
1
/2 in. (13mm) dia. plated steel.
SMD-301
Smoke Dampers
Steel Airfoil Blades
UL 555S Leakage Class I
Model SMD-301 meets the requirements for smoke
dampers established by:
National Fire Protection Association
NFPA Standards 92A, 92B, 101 & 105
IBC International Building Codes
New York City (MEA listing #260-91-M)
CSFM California State Fire Marshal
Leakage (Smoke) Damper Listing (#2330-0981:104)
“UL CLASSIFIED (see complete marking on
product)”
“UL CLASSIFIED to Canadian safety standards
(see complete marking on product)”
Standard 555S (Listing #R13317)
Greenheck Fan Corporation certifies that the
model SMD-301 shown herein is licensed to
bear the AMCA Seal. The ratings shown are
based on tests and procedures performed
in accordance with AMCA Publication 511
and comply with the requirements of the
AMCA Certified Ratings Programs. The
AMCA Certified Ratings Seal applies to air
performance ratings only.
Size Limitations:
Minimum Size:
(203mm W x 152mm H)
Maximum Size:
Single Section: 32 in. W x 50 in. H
(813mm W x 1270mm H)
Multiple Section: 128 in. W x 100 in. H
(3251mm W x 2540mm H) or
256 in. W x 50 in. H
(6502mm W x 1270mm H)
8 in. W x 6 in. H
LH
Optional Features:
• Galvanized steel sleeves.
• Stainless steel bearings
• OCI (Open closed indication switches)
• Electric or pneumatic actuators to accomplish smoke
management and system functions.
• Transitions (R, C, O)
• POC retaining angles
• Momentary Switch
• Smoke detectors
• Sealed transitions and sleeves
• Fail open
Installation instructions available at www.greenheck.com
*W&H dimensions furnished approximately 1/4 in. (6mm) undersize.
Right hand drive is shown. Left hand drive is available upon request.
Damper also may be rotated 180° in the field for opposite side drive.
(Add sleeve thickness for overall sleeved damper dimension)
RH
Pressure Drop Data SMD-301
5D 6D
5D
D
4 (W) (H)
3.14
5D 6D
5D
D
4 (W) (H
)
3.14
This pressure drop testing was conducted in accordance with AMCA Standard 500-D using the three configurations shown. All
data has been corrected to represent standard air at a density of .075 lb/ft3 (1.201 kg/m3).
Actual pressure drop found in any HVAC system is a combination of many factors. This pressure drop information along with an
analysis of other system influences should be used to estimate actual pressure losses for a damper installed in a given HVAC
system.
AMCA Test Figures
Figure 5.3 Illustrates a fully ducted damper. This configuration has the lowest pressure drop of the three test configurations
because entrance and exit losses are minimized by straight duct runs upstream and downstream of the damper.
Figure 5.2 Illustrates a ducted damper exhausting air into an open area. This configuration has a lower pressure drop than
Figure 5.5 because entrance losses are minimized by a straight duct run upstream of the damper.
Figure 5.5 Illustrates a plenum mounted damper. This configuration has the highest pressure drop because of extremely high
entrance and exit losses due to the sudden changes of area in the system.
Figure 5.3
Figure 5.2
Figure 5.5
12x12
48x12
24x24
36x36
12x48
AMCA 5.2 Pressure Drop SMD-301
5D 6D
5D
D
4 (W) (H)
3.14
Ve locity
(fpm)
Pressure Drop
(in. wg)
Ve locity
(fpm)
Pressure Drop
(in. wg)
Velocity
(fpm)
Pressure Drop
(in. wg)
Ve locity
(fpm)
Pressure Drop
(in. wg)
Ve locity
(fpm)
Pressure Drop
(in. wg)
500 0.03 500 0.01 500 0.01 500 0.01 500 0.02
1000 0.12 1000 0.06 1000 0.061000 0.051000 0.08
1500 0.26 1500 0.12 1500 0.121500 0.12 1500 0.18
2000 0.46 2000 0.22 2000 0.222000 0.21 2000 0.33
2500 0.72 2500 0.34 2500 0.342500 0.332500 0.51
3000 1.04 3000 0.49 3000 0.493000 0.483000 0.74
3500 1.41 3500 0.67 3500 0.673500 0.653500 1.00
4000 1.84 4000 0.87 4000 0.884000 0.854000 1.31
12in. X 48 in.
305mm x 1219mm) 48 in. x 12 in. (1219mm x 305mm) 24 in. x 24 in. (610mm x 610mm) 36in. x 36 in. (914mm x 914mm) 12 in. x 12 in. (305mm x 305mm)
* Sizes are in inches.
Greenheck Fan Corporation certifies that the
model SMD-301 shown herein is licensed to bear
the AMCA Seal. The ratings shown are based on
tests and procedures performed in accordance
with AMCA Publication 511 and comply with
the requirements of the AMCA Certified Ratings
Programs. The AMCA Certified Ratings Seal
applies to air performance ratings only.