The Whole House Ventilation System from Vent-Axia is a single module that continuously ventilates the property. Automatic control option with humidity sensors. It can also be used to improve the indoor air quality. There are models to suit all property types and sizes:. Specifications: 240V. Spigot dia: 100 or 125mm. Extraction Rate: 443mm?/hour. Associated products: 77077 and 29928.