An Energy Recovery Ventilator (ERV) is a type of ventilation system used to improve the air quality in a home or commercial building. It works by exchanging the stale, indoor air with fresh, outdoor air while also recovering the energy from the stale air. This helps to reduce energy costs and improve the overall air quality in the building. ERV manufacturers produce a variety of models to suit different needs and budgets. The most common type of ERV is a counterflow heat exchanger, which uses two fans to exchange air between the inside and outside of the building. The fans move the air in opposite directions, allowing the energy from the outgoing air to be transferred to the incoming air. This helps to reduce the amount of energy needed to heat or cool the building. ERV manufacturers also produce systems that use other types of heat exchangers, such as plate heat exchangers and rotary heat exchangers. These systems are more efficient than counterflow heat exchangers, but they are also more expensive. ERV systems are an effective way to improve air quality and reduce energy costs in a home or commercial building.