The variable air volume (VAV) system, as the name implies, apart from all regular functions and features of CAV System, have extra controls that vary the airflow depending on the position of the sash but keep the face velocity constant. These fume hoods employ a movable damper in the ductwork to achieve a consistent face velocity by adjusting the airflow. Since, numerous fume cupboard ventilation systems operate as full fresh air types, a substantial amount of energy is often wasted when these fume cupboards are idle.

This type of system, which can be fitted as part of a new installation or retrofitted to any existing laboratory, has several significant benefits.

Energy efficiency – With a VAV system in place, fume cupboards operate at minimal exhaust volumes when the sash is closed, ensuring that energy usage is highly responsive to user needs. The actual savings vary based on user behaviour, but, in general, the less the hoods are open (both in terms of height and duration), the more substantial the energy savings.

Carbon emissions reduced

Cost saving – Although VAV systems may involve higher initial costs compared to CAV systems, real-world experience shows that customers who install VAV controllers can achieve up to an 80% reduction in energy costs. This efficiency translates to a rapid return on investment, making the initial costs quickly offset by the energy savings.

Comfort – A VAV system does not affect the temperature of the lab, leading to more comfort

Improved safety – Variable Air Volume (VAV) systems offer enhanced protection for Laboratory occupants against potentially hazardous fumes and substances, aiding in compliance with pertinent health and safety regulations.