Demand Controlled Mechanical Extract Ventilation (MEV) system continuously extracts stale, polluted air from rooms where most moisture is generated (e.g. kitchens and bathrooms). The low energy unit runs continuously at a low normal ventilation rate and when higher humidity is detected (i.e. when showering) the system automatically boosts.
You can make significant energy savings as there is no need for noisy, multiple extractor fans in each wetroom which create multiple breakout points in the building, creating draughts, air leakage and heat loss. It is also much more economical to run one fan instead of multiple single fans. With a three year product warranty, the high quality EC motor has a long-lasting performance, compared to low cost wall fans (some of which have a limited life cycle).