Mechanical Ventilation and Heat Recovery (MVHR) is a system for whole house ventilation that supplies and extracts air throughout the whole of the property. It offers a balanced low energy ventilation solution for new dwellings and re-uses up to 95% of the heat that would have otherwise have been lost. Integration with a whole house control system provides for optimum use of an MVHR unit such as boosting ventilation if a humidity sensor detects a higher than normal humidity level.
As building efficiency is improved with insulation and weather stripping, buildings are intentionally made more airtight, and consequently less well ventilated. HRV systems provide ventilation without the loss of heat or humidty, which could put stress on a building’s heating, ventilating/ventilation, and air conditioning (HVAC) systems. HRV introduces fresh air to a building and improves climate control, whilst promoting efficient energy use.
UK building regulations require one air change every two hours (0.5 ACH). With traditional extract-only ventilation that means a house boiler would need to warm up a house-full of cold air 12 times a day.