Size the louver at too high free area velocity and run the risk of water penetration. Size the louver to prevent water penetration and the low free area velocity requires a much larger louver bank be used. In applications where wind driven rain penetration is a problem, the ASL 6 offers the solution. The ASL4 louver has been selected as the preferred rain eliminator product for air cooled electric motors and generator houses by industry leaders in the manufacturing of ocean going oil platforms. The revolutionary NEW ASL 12 Hurricane Louver has been designed and tested to the strict Dade County, Florida, code for hurricane capability.
Wind driven sand creates an entirely different problem from wind driven rain.
The ASL8 was designed to capture sand particles and remove them without the need for bleed fans to eliminate the collected sand. Higher efficiencies and higher free area velocities mean smaller banks of sand louvers. Air handler manufacturers are finding that the ASL4 and ASL6 series can eliminate water carryover from wind driven rain and even heavy fog. Because the free area velocity through the louver can be increased dramatically, up to 4,000 fpm, without significant pressure drop penalties, intake louver sizes are greatly reduced. The reduction of intake louvers coupled with the removal of water carryover, has given these OEM customers a competitive edge.