The active chilled beam system works on the principle of using a chilled water heat exchanger installed in a terminal in the ceiling to offset the sensible cooling loads in the occupied space. The system uses primary conditioned air introduced through the chilled beam terminal for ventilation and humidity control and to create the induction of room air through the terminal heat exchanger using special air nozzles
The system provides substantial energy savings because it uses relatively high chilled water temperatures in the terminal heat exchanger resulting in large savings in the running costs of the system water chillers. It also allows the heat exchanger to run dry thereby avoiding the maintenance and hygiene issues associated with the condensate drainage from other terminals like fan coil units. There are further large savings in fan energy to move air around the building because the system does not rely on air to offset the sensible cooling loads and therefore the primary air quantity can be reduced to only that needed for ventilation, humidity control and to operate the nozzles for the induction process.
This system has become very popular in Europe due to its energy saving capability and also because the amount of air flow required is very low and as such 100% fresh air can be used for the primary air source. This results in excellent air quality and also makes the system very suitable for hospitals and medical facilities which want to eliminate recirculated air which can result in cross contamination.