Constant Air Volume (CAV)
Heating, ventilating, and air-conditioning (HVAC) system. Generally, CAV systems are small used for a single thermal zone however, variations such as CAV Multizone, CAV with reheat, and CAV primary-secondary systems can serve multiple zones and larger buildings.
Cooling device using natural heat convection, circulating air through a building with no air handlers, ductwork or noise. Chilled Beams are a form of radiator using an external source for cooling, they act as a heat sink for rising warm air, cooling it, causing it to descend.
A mixed mode system combines the best aspects of both natural ventilation and mechanical ventilation/air conditioning. The simplest example of a mixed mode system is the opening of windows to enable natural ventilation with air conditioning available when windows cannot be opened.
Ventilation systems are considered natural if the air is supplied and removed from the indoor space by non-mechanical means. The use of natural ventilation reduces the need for mechanical energy consuming plant and is therefore more efficient. The requirement for natural ventilation to be utilised effectively in a building calls for early implementation in the design of a building.
Variable Air Volume (VAV)
Variable air volume (VAV) is a technique used to control heating, ventilating, and/or air-conditioning (HVAC) system. A basic VAV system uses one supply duct that distributes cooled air.
Variable Speed Drive (VSD)
Electronic device used with a motor providing variable flow, reducing output from the motor and increasing its efficiency.