Greenheck Fan WD-400 User Manual

Airflow

*H

Model WD-400

No Flange

Airflow

*H

Model WD-430

Flange on Intake

Airflow

*H

Model WD-420

Flange on Discharge

Airflow

*H

Model WD-410

No Flange

1

1

/2 in

.

4

5

/

8

in

.

M

a

x.

3 3/8 in

.

4

5

/

8

in

.

M

a

x.

3 1/2 in

.

4

5

/

8

in

.

Max.

3

1

/

2

in

.

1

1

/

2

in

.

1

1

/

2

in

.

1

1

/

2

in

.

3

3

/

8

in

.

3

3

/

4

in

.

Max.

H*

W*

Triple Panel

Double Panel

Single Panel

H*

H*

W*

W*

WD-400 SERIES

Non-Motorized Backdraft Damper

Horizontal or Vertical Mount (Intake)

Application and Design

The WD-400 series are non-motorized backdraft dampers which may be mounted either vertically for intake air or mounted
horizontally to allow vertical airflow down and prevent reverse airflow. The dampers are opened by air pressure differential and

closed by springs. Optional motor packs are not available.

Ratings (See page 2 for specific limitations)
Pressure: 2.0 in. wg (498 Pa) - differential

pressure

Velocity: 2500 fpm (13 m/s)

Temperature: 180°F (82ºC)

Standard Construction

Frame: 18 ga. (1.3mm) galvanized steel

Blades: 0.025 in. (0.64mm) aluminum

Axles: 3/16 in. (4.8mm) dia. zinc plated steel

rod, full length

Bearings: Synthetic (acetal)

Linkage: 0.064 in. (1.6mm) 6061T6 aluminum

tie bar

Blade Seals: Vinyl

Size Limitations (see pages 3 & 4 for specific

limitations)

Minimum Panel Size
8 in. W x 8 in. H

(203mm x 203mm)

Maximum Panel Size

Single Panel: 31 in. W x 74 in. H
(787mm x 1880mm)
Double Panel (WD-400/410): 50 in. W x 74 in. H
(1270mm x 1880mm)
Double Panel (WD-420/430): 63 in. W x 74 in. H
(1600mm x 1880mm)
Triple Panel (WD-420/430): 74 in. W x 74 in. H
(1880mm x 1880mm)

Options and Accessories (at additional cost)

• 11/2 in. (38mm) flange on discharge: WD-420

• 11/2 in. (38mm) flange on intake: WD-430

• Stainless Steel Axles

*W & H dimensions furnished
approximately 1/8 in. (3mm) under size.

1 2 3 4 5 6 7 8 9 1 0 20 30 40 50 60 70 80 90 100 150

Static Pressure Difference (In. wg)

Air Leakage in cfm/ft

2

1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

8.5

8.0

7.0

6.0

5.0

4.0

3.0

2.0

Velocity (fpm)

1

x 10

Pressure Loss ( in. wg)

2 3 4 5 6 7 8 9 10

x 100

2 3 4 5 6 7 8 9 10

x 1000

2 3 4 5 6 7 8 9 10

Start Open

Full Open

10.0

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.10

0.09

0.08

0.07

0.06

0.05

0.04

0.03

0.02

Velocity (fpm)

1

x 10

Pressure Loss (in. wg)

10.0

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

2 3 4 5 6 7 8 9 10

1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.10

0.09

0.08

0.07

0.06

0.05

0.04

0.03

0.02

x 100

2 3 4 5 6 7 8 9 10

x 1000

2 3 4 5 6 7 8 9 10

Start Open

Full Open

WD-400 SERIESPERFORMANCE DATA

Pressure Drop

Performance data results from testing a 36 in. x 36 in. (914mm x 914mm) damper in accordance with AMCA Standard 500-D
using Figure 5.3 for the WD-400 and Figure 5.7A for the WD-410. All data has been corrected to represent standard air at 0.075
lb/ft3 (1.201 kg/m3).

∆P Velocity
Operational Data

(Pa) (m/s)

Blades Start to Open 0.026 250
(6.5) (1.3)

Blades Fully Open 0.04 1200
(10) (6.1)

WD-400

in. wg fpm

WD-410

∆P Velocity
Operational Data

(Pa) (m/s)

Blades Start to Open 0.014 22
(3.5) (0.1)

Blades Fully Open 0.12 1000
(30 Pa) (5.1)

in. wg fpm

Leakage

Leakage testing was conducted in accordance with AMCA
Standard 500-D and is expressed as cfm/ft2 of damper face
area. All data has been corrected to represent standard air at

0.075 lb/ft3 (1.201 kg/m3).

36 in. x 36 in. (914mm x 914mm) Damper

Pressure Drop

36 in. x 36 in. (914mmx 914mm) Damper

Pressure Drop

Leakage

36 in. x 36 in. (914mm x 914mm) Damper

2