Louver Selection and Application

FREE AREA CHART (SQUARE FEET)LouverLouver

HeightLouver Width In InchesHeight

Inches120114108102969084787266605448423630241812Inches

124.033.823.623.413.213.002.802.592.392.181.981.771.571.361.160.950.740.540.3312

186.906.556.205.855.495.144.794.444.093.743.383.032.682.331.981.631.270.920.5718

249.779.288.788.287.787.286.796.295.795.294.794.303.803.302.802.301.811.310.8124

3013.3812.7012.0211.3310.659.979.298.617.937.246.565.885.204.523.833.152.471.791.1130

3616.3515.5214.6913.8513.0212.1911.3510.529.698.858.027.196.355.524.693.853.022.191.3536

4219.3318.3417.3616.3715.3914.4013.4212.4311.4510.469.488.497.516.525.544.553.572.581.6042

4822.3021.1620.0318.8917.7516.6215.4814.3513.2112.0710.949.808.667.536.395.264.122.981.8548

5425.2723.9822.7021.4120.1218.8317.5516.2614.9713.6812.3911.119.828.537.245.964.673.382.0954

6028.2526.8125.3723.9322.4921.0519.6118.1716.7315.2913.8512.4110.979.548.106.665.223.782.3460

6630.5929.0327.4825.9224.3622.8021.2419.6818.1216.5615.0013.4511.8910.338.777.215.654.092.5366

7233.4731.7630.0628.3526.6424.9423.2321.5319.8218.1216.4114.7113.0011.309.597.896.184.482.7772

7836.3434.4932.6330.7828.9327.0825.2323.3821.5219.6717.8215.9714.1212.2710.428.566.714.863.0178

8439.2137.2135.2133.2231.2229.2227.2225.2223.2321.2319.2317.2315.2313.2411.249.247.245.243.2584

9042.0839.9437.7935.6533.5031.3629.2227.0724.9322.7820.6418.4916.3514.2112.069.927.775.633.4890

9644.9542.6640.3738.0835.7933.5031.2128.9226.6324.3422.0519.7617.4715.1812.8810.598.306.013.7296

10248.5746.1043.6241.1538.6736.2033.7231.2528.7726.3023.8221.3518.8716.4013.9211.458.976.504.02102

10851.5548.9246.2943.6741.0438.4135.7933.1630.5327.9125.2822.6520.0317.4014.7712.159.526.894.27108

11454.5251.7448.9646.1943.4140.6337.8535.0732.3029.5226.7423.9621.1818.4115.6312.8510.077.294.51114

12057.4954.5651.6348.7145.7842.8539.9236.9934.0631.1328.2025.2722.3419.4116.4813.5510.627.694.76120

FL-D-2 Selection and ExamplesExample 2:Example 1:Louver size given as 66" w x 54" h intake - determineAirflow given as 10,000 cfm - select louver size.

maximum airflow.A. Determine louver free area by dividing airflow by

free area velocity (do not exceed 928 fpm on intake

A. Use Free Area Chart to determine louver application).

Free Area = 13.62 ft.2

10,000 cfm ÷ 805 fpm = 12.42 ft.2

B. Multiply Free Area x Free Area Velocity (do Required Louver Free Area VelocityAirflow

not exceed 805 fpm on intake louver Free Area

applications).B. Select a louver with at least the required louver free

13.62 ft2 x 805 fpm = 10,964 cfm area from Free Area Chart above.

Maximum AirflowFree Area VelocityFree Area60" w x 48" h

12.42 ft. free area

C. Check the pressure drop of the selected 805 fpm free area velocity (10,000) cfm ÷

louver at the given airflow (Airflow 12.42 ft.2 F.A.

Resistance Chart on Page 2).(Other selections available - See Free Area Chart above.)

D P at 928 fpm = .126 in w.g.

Pressure DropFree Area VelocityC. Check the pressure drop of the selected louver

at the selected louver given airflow (Airflow Resistance Chart on Page 2).

! P at 919 fpm = 0.125 in w.g.

Pressure DropFree Area Velocity