In the winter, conventional make-up air systems have to heat the cold outside air prior to introduction into the building. This is an expensive process in both equipment and continuing energy cost. The Power Tube Fam Make-Up Air System is a simplier system that utilizes wasted building heat and basic earodynamic principles for supplying, tempering and distributing make-up air. And that makes it less expensive than conventional make-up air systems to purchase, to install and to operate.

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