Chilled beam

A chilled beam is a type of convection HVAC system designed to heat or cool large buildings. Pipes of water are passed through a "beam" (a heat exchanger) either integrated into standard suspended ceiling systems or suspended a short distance from the ceiling of a room. As the beam chills the air around it, the air becomes denser and falls to the floor. It is replaced by warmer air moving up from below, causing a constant flow of convection and cooling the room. Heating works in much the same fashion, similar to a steam radiator. There are two types of chilled beams. Some passive types rely solely on convection whilst there is a "Radiant"/convective passive type which cools through a combination of radiant exchange (40%) and convection (60%) which can provide higher thermal comfort levels, while the active type (also called an "induction diffuser") uses the momentum of ventilation air entering at relatively high velocity to "induce" circulation of room air through the unit (thus increasing its heating and cooling capacity).