TEK-Plenum-051815-body.jpgContinental Fan's TEK Plenum Fans feature TEK backward curved airfoil wheels. The impellers combine precision injection molding techniques with modern high-strength plastics to produce a wheel that is stronger than steel, yet half its weight, according to the company. TEK Plenum Fans are designed to slide into field erected or factory built air handling units or plenums. They operate by pressurizing the plenum in which they operate, and they are suited for supply or return air applications. This design saves space by eliminating traditional scroll housings, transitions, and diffusers normally found within a plenum.