To determine leakage at static pressure differentials higher than 1 inch water gage, multiply leakage at 1 inch (determined from the Damper Leakage Table) by correction factor for higher static pressure (determined from the Correction Factor Table).
Leakage ratings are based on AMCA Standard 500 using Test Setup Apparatus Figure 5.5. Torque applied holding damper closed at 10 lb·in./sq. ft (0.1216 kPa) of damper with minimum of 20 lb·in (2.26 N·m).
Dampers may tolerate higher pressures and velocities than those listed here. Conservative ratings are presented intentionally in an effort to avoid misapplication. Consult Johnson Controls when damper is to be applied in conditions exceeding recommended maximums.
Damper Width | Maximum System Pressure, in. w.g. (kPa) | Maximum System Velocity | Leakage with Seals | Leakage without Seals | ||
---|---|---|---|---|---|---|
% of Maximum Flow | Total cfm (lps) | % of Maximum Flow | Total cfm (lps) | |||
72 in. (1,829 mm) |
13.0 (3.25) | 6,000 feet per minute (30.48 meters per second) | 0.035 | 60 (28) | 0.162 | 275 (130) |
60 in. (1,524 mm) |
13.0 (3.25) | 0.038 | 45 (21) | 0.191 | 225 (106) | |
48 in. (1,219 mm) |
13.0 (3.25) | 0.046 | 35 (16.5) | 0.232 | 175 (82.5) | |
36 in. (914 mm) |
14.0 (3.50) | 0.066 | 28 (13) | 0.294 | 125 (59) | |
24 in. (610 mm) |
15.0 (3.75) | 0.132 | 25 (11.7) | 0.451 | 85 (40) | |
12 in. (305 mm) |
17.0 (4.25) | 0.318 | 15 (7) | 1.060 | 50 (23.6) |
Static Pressure, in. w.g. (kPa) | Correction Factor |
---|---|
1 (0.25) | 1.0 |
2 (0.50) | 1.4 |
3 (0.75) | 1.7 |
4 (1.0) | 2.0 |
5 (1.25) | 2.2 |
6 (1.5) | 2.4 |
7 (1.75) | 2.6 |
8 (2.0) | 2.8 |
9 (2.25) | 3.0 |
10 (2.50) | 3.2 |
11 (2.75) | 3.3 |
12 (3.0) | 3.5 |
13 (3.25) | 3.6 |
14 (3.50) | 3.7 |
15 (3.75) | 3.9 |
16 (4.0) | 4.0 |
17 (4.25) | 4.1 |