How Balanced Home Ventilation Keeps You Comfortable
Balanced home ventilation means exhausting stale indoor air and inducting fresh outdoor air in equal volume, without impacting indoor temperatures. Usually, that won’t happen simply by opening windows. Standard exhaust fans can remove too much indoor air, depressurizing the house and drawing in unfiltered hot outdoor air in summer and cold air in winter. Balanced home ventilation utilizes a technology called a heat recovery ventilator (HRV) to ensure that incoming and outgoing ventilation are equalized and temperature-controlled. Here’s how balanced ventilation keeps your indoor air quality comfortable and healthy in all seasons:
- An HRV system incorporates dedicated small-diameter ductwork to supply and remove air from living spaces. Both sides of the system connect to a central controller that includes twin fans and a heat exchanger.
- Exhaust ducts take stale air from areas such as the kitchen, bathrooms and utility rooms and channels it through the central controller before exhausting it to the exterior of the house. Meanwhile, the intake stream inducts an exactly equal volume of fresh outdoor through the controller and distributes to bedrooms, living rooms and other common areas of the house.
- Inside the controller, the heat exchanger transfers heat from the warmer air stream to the cooler stream. In summer, heat energy is extracted from hot incoming outdoor air and added to the cooler exhaust stream as it leaves the house, reducing the cooling load on your air conditioner and lowering costs. In winter, the reverse occurs: heat produced by your furnace is removed from the exhaust stream and transferred to pre-warm incoming cold, fresh air from the outdoors. As much as 90 percent of the heat energy can be recovered to minimize furnace cycles and keep heating costs low.
- A variant known as an energy recovery ventilator (ERV) transfers heat just like an HRV but also extracts water vapor from the more moist air stream, transferring it to the drier stream. This reduces infiltration of excess outdoor humidity in summer and makes the indoor environment less dry in winter.