Heating, ventilation, and air conditioning system, an HVAC system is composed of mechanical and electrical equipment that provides heating, cooling, and air quality control for a building. In modern buildings where at least one tenant is a business whose function involves keeping records, computer equipment, and sensitive electronics are often housed in a raised floor structure inside the conditioned space. The HVAC system supplies the heat exchangers with filtered outside air for direct cooling or heating of the raised floor structures using multiple supplies and returns plenums to distribute conditioned air.

A raised floor is a grid of metal strips forming a platform between surrounding floor and ceiling surfaces used to conceal the space below. Raised floor structures are often installed in conditioned spaces such as computer rooms, telecommunications equipment rooms, and electrical equipment areas (EEAs) in order to facilitate the cooling of sensitive electronic devices with outside air instead of recirculated air. The metal flooring provides a level, flat surface that enables easy installation of equipment support systems such as Ciscos Integrated Service Routers (ISRs) and Switches.