Project Images The Horace Mann Cos. retro-commissioning Project Summary Hanson provided retro-commissioning services at The Horace Mann Cos.’ headquarters in Springfield, Illinois. The 189,000-square-foot, six-story structure was built in 1972. The building has central chilled water and steam and hot water systems. Low-pressure steam boilers, chillers, pumps, cooling towers and steam and hot water heat exchangers are located at the mechanical penthouse level. The air distribution system consists of constant volume reheat boxes for the center core of the building for floors two through six, and some areas at the lower level. The first level and other areas at the lower level have hot water reheat coils. The perimeter areas of floors two through five are served by induction units equipped with hydronic coils that circulate hot water in winter and chilled water in summer. One large air handler in the penthouse serves the perimeter induction system, while another large air handler in the penthouse serves the center core of floors two through six and some areas at the lower level. Three additional air handlers in the basement mechanical room serve areas at the lower level and the first level. Hanson completed the investigation phase of the project and identified eight energy conservation measures, representing savings of more than 20 percent of Horace Mann’s annual utility spending. The study was completed as part of a retro-commissioning rebate program sponsored by Horace Mann’s electric utility company.