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Heat/Energy Recovery Ventilators – Introduction

A Heat Recovery Ventilator (also known as HRV) consists of two separate air-handling systems – one collects and exhausts stale indoor air; the other draws in outdoor air and distributes it throughout the home. HRVs provide fresh air at a reduced cost, while also saving energy by reducing the heating (or cooling) requirements. Energy Recovery Ventilators (ERVs) are closely related, however ERVs also transfer some of the humidity (or moisture) of the exhaust air to the intake air.

Heat Recovery Ventilator (HRV)

An HRV is a mechanical ventilation device that helps make your home healthier, cleaner and more comfortable by continuously replacing stale indoor air with fresh outdoor air. HRVs are set apart from other mechanical ventilation devices by their ability to exchange heat between the supply and exhaust air streams, which in turn reduces the cost of heating or cooling the healthy fresh air that circulates through the home. HRVs are sometimes called air-to-air heat exchangers because they preheat or cool incoming air using exhaust air.

In recent years, more and more existing homes have undergone energy-efficiency improvements such as upgraded insulation, improved air sealing, the installation of energy-efficient windows, doors and heating systems, etc. As well, improved practices in new home construction have resulted in more energy-efficient and airtight conventional homes.

In many of these homes, air infiltration through doors, windows and other openings in the building shell is too random and does not always provide adequate ventilation. Even when there is an acceptable rate of air exchange, the fresh air may not be getting to the rooms where it is needed. As a result, mechanical ventilation is needed in many conventional homes in order to evenly distribute fresh air throughout the home and maintain a healthy living environment. An added benefit of mechanical ventilation systems is their capability to filter the incoming fresh outdoor air.

More information on a HRV.