Negative Pressure Air Filtration Systems
CarlisleIT offers three types of negative air pressure filtration systems. These systems significantly reduce the ingression of cooling air contaminants entering the equipment with top to bottom cooling flows.
Negative Pressure Air Filtration Systems

Model AF-5000
The AF-5000 fits over the top of the INU, covering air holes in the rear panel and sides. ARINC 561 downdraft cooling air passes through the filter cartridge before entering the INU cooling holes.

Model AF-5000 Features
- Flight trials and design enhancements have resulted in a unit package size compatible with most transport aircraft configurations
- Over 5 years of flight trials and in-service experiences have shown lower INU removal rates after Air Filtration Unit installation
- Significantly reduces the amount of dirt, water, and other potentially conductive contaminants from entering the INU
- No significant reduction in air flow through the INU
- Maintains minimum air flow necessary to meet INU cooling requirements
- Customized sealing design deters water ingression
- Uses a disposable filter cartridge that has a high dust arrestor capability and low air resistance
- Based on the unique design and functionality of the AF-5000, ECS has been awarded U.S. Patent Number 5,298,045
- The AFU design allows for easy installation (no special tools or training required)
- Filter cartridge is replaceable either on the aircraft or in a hanger
- Replacement interval is dependent upon aircraft operating environment
- The AF-5000 Air Filtration Unit and Replacement Filter Cartridges can be ordered separately