A heat recovery ventilator is a ventilation system that helps to improve indoor air quality while also increasing energy efficiency. The main function of a heat recovery ventilator (HRV) is to exchange stale indoor air with fresh outdoor air while minimizing heat loss or gain. HRV’s are most commonly seen in residential and commercial buildings. HRV’s help to lower your energy bill and improve energy efficiency. They also help to remove humidity, odors, and pollutants from a building.