Demand controlled ventilation (DCV) is a method providing automatic regulation to the ventilation system dependent upon the needs of air change rates (occupancy, pollution loads, etc.) using a suitable sensor and without user intervention i.e. automatic.
This approach can be applied to any of the system types above and has been very popular in Europe for decades. Demand Control is now a common feature of quality s continuous mechanical extract ventilation and passive stack ventilation systems.
With DCV systems, extract and supply air flow rates can be regulated to ventilate where and when needed, achieving an overall reduction in air renewal and associated heat losses. Scientific studies carried out in France demonstrate that DCV can result in at least 30% reduction in ventilation losses compared to natural ventilation with conventional extract fans. It can also reduce the primary energy use of associated fans. Extensive monitoring also shows that demand-controlled mechanical extract ventilation achieves excellent indoor air quality.
