A Variable Air volume (VAV) system is an HVAC system that controls temperature within a space by varying the volumetric flow of heated or cooled supply air to the space. Normally, the supply air from the air handler is cooled and passes though a thermostatically-controlled VAV box (volume control box) before entering the space. The VAV box will have a minimum position setting to ensure adequate ventilation air at all times, and may be equipped with a reheat coil for those times when heat from people, lighting, and equipment in the space will not be adequate.