Energy recovery ventilators (ERV) constantly supply fresh air to provide a healthy indoor environment by reducing odors and and indoor pollutants, such as radon, formaldehyde, tobacco smoke, nitrogen dioxides, carbon monoxide, and pesticides. Energy recovery units constantly bring fresh air into the home while exhausting like amounts of stale indoor air at the same time.
The recovery part of the ventilation means that the hot or cold energy in the air (depending on the season) is extracted from the indoor air before it is exhausted and transferred to the incoming air, so that there is little energy lost.
ERV vs HRV
Heat recovery ventilators (HRV) will transfer temperature only from the high temperature air to the low temperature air. Energy recovery ventilators (ERV) transfer both temperature and moisture. Since transferring both temperature and moisture has benefits in both winter and summer, ERV's are a better choice in all but the most northern colder climates for providing year round fresh air to the home.
Energy recovery units can be installed in an existing home, as well as a new home, and are an integral part of the heating and air conditioning system. ERV systems can work with any forced air system equipped with a blower and duct system. It can also be used with non-forced air systems (floor heat coils, for instance) as an independent system.