RectorSeal has announced the asset purchase of Airtec Products Corp. of Fall River, Mass.

The Criti-Clean fan filter unit (FFU), a fan-powered laminar flow HEPA filter diffuser, is a computer-controlled FFU. It features a variable-speed electronically commutated motor, stainless steel construction, and an all-welded plenum built to meet the latest pressure testing standards.

Sweating presents itself in an air distribution system as moisture that forms on the faces of lay-in diffusers and T-bar grids adjacent to those diffusers, where this moisture collects and drips into the areas below. While sweating may be a simple annoyance, it may also be potentially dangerous. Either way, it is a symptom of a larger problem.

Most new installations of grilles and diffusers involve a suspended ceiling grid, but some installations require surface mounting. Square ceiling diffusers and filter grilles can present the biggest challenge. Here are some recommended guidelines and solutions.

The new AxiTop diffuser for 800 and 910mm axial fans improves both air performance and reduces noise, says ebm-papst.