Multistack manufactures modular and conventional chillers, modular geothermal heat pumps, modular air-to-water heat pumps, and modular Dedicated Heat Recovery Chillers (DHRC) in Sparta, Wisconsin. Multistack focuses on high-efficiency, low-impact chiller solutions using less and safer refrigerants, and fossil fuel alternatives. Multistack is an environmentally-conscious manufacturer, providing the HVAC industry's highest cooling and heating output per pound. Multistack is the originator and innovator of the modular chiller concept. Product innovation based on customer input is Multistack's prime focus, holding several patents including the original modular chiller concept, Dedicated Heat Recovery Chiller control, and other advances in modular and conventional chillers. Multistack has a broad product offering and not only builds air- and water-cooled chillers but also MRI chillers, water-cooled condensing units and tactical chillers for defense applications. With its MagLev compressor, Multistack remains the pioneer in the application of oil-free magnetic levitation compressor technology in the chiller environment.