Ventilation systems like Energy Recovery Ventilators (ERVs) and Heat Recovery Ventilators (HRVs) are essential parts of any modern home and can seriously impact indoor air quality and comfort.
According to the EPA, Americans spend up to 90 percent of their time indoors, where the air quality can be two to five times worse than outside. So, all homes, both new and old, need a ventilation method, like an ERV or HRV, to exchange stale and fresh air and maintain acceptable indoor air quality.
Whether you're a homeowner, a facility manager, or a ventilation professional, you need to understand how to choose the right ERV or HRV for your space, climate, and needs. This buying guide will explain everything needed to purchase the right ERV or HRV.
- Understanding ERVs and HRVs
- How to Choose Between an ERV and an HRV
- Sizing an ERV or HRV for Your Home
- Installation Considerations
- Top ERV and HRV Brands
- Sylvane's Expert Take
Understanding ERVs and HRVs
ERVs and HRVs are designed to improve indoor air quality while conserving energy to maintain a comfortable living environment. Choosing the right ventilation system to keep that balance starts with understanding what ERVs and HRVs are and how they function.
What is an Energy Recovery Ventilator (ERV)?
An Energy Recovery Ventilator is a device that exchanges both heat and moisture between the incoming fresh air (outdoor air) and the outgoing stale air (exhaust air). This dual exchange process refreshes the indoor environment and helps maintain ideal humidity levels.
Inside, the core of the ERV (the heat exchanger) facilitates the transfer of heat and moisture, balancing indoor temperatures and humidity levels. This process ensures a comfortable and energy-efficient home environment.
What is a Heat Recovery Ventilator (HRV)?
A Heat Recovery Ventilator focuses on transferring heat between air streams without affecting moisture levels. This makes HRVs ideal for climates where humidity control is less of a concern.
Similar to ERVs, HRVs draw in outdoor air and expel indoor air. However, an HRV core is designed for only heat transfer. This helps retain indoor warmth during cold seasons and expel hot air during warm seasons, contributing to energy savings and maintaining comfort.
How to Choose Between an ERV and an HRV
While both systems can improve air quality and comfort and increase energy efficiency, the key differences between ERVs and HRVs are humidity and climate.
- HRVs: Since HRVs recover only necessary heat without affecting humidity levels, these specialized systems efficiently maintain indoor temperature, especially in colder, drier climates.
- ERVs: Comparatively, ERVs recover heat and humidity, providing added benefits in humid or arid regions with extremely high or low humidity levels. Homes or buildings with high humidity-generating activities, such as cooking or showering, may benefit from an ERV.
Sizing an ERV or HRV for Your Home
Choosing the correct size for your home or building is crucial to taking advantage of these specialized systems' energy efficiency and optimal performance. An ERV or HRV that is too large or too small can lead to inefficiencies and increased energy costs, so you will want to choose a system that matches your home's specific needs. Typically, homeowners will need to consult with a ventilation professional before choosing one of these systems, but you should know a few metrics while selecting a system.
- Airflow CFM: Most ventilation fans are rated by their airflow cubic feet per meter (CFM) specification. The true CFM requirements of a home can be calculated using many different online resources, like Fantech's Fresh Air Appliance Selector. But, a good rule of thumb for most homes with typical eight-foot ceilings is 5 CFM per 100 square feet of floor area. So, for an average 2,000-square-foot home, you would want a system with an airflow capacity of about 100 CFM.
- Air Changes per Hour (ACH): Air changes per hour measure the number of times indoor air is replaced by fresh outdoor air each hour. According to the EPA, most organizations recommend a system that can provide between 0.35 and 5 ACH for residential spaces.
Other factors, like the home layout, number of occupants, and regional building codes, will impact the ERV and HRV system CFM requirements for your specific home, so we recommend consulting with a ventilation system professional before selecting a system.
Installation Considerations
Proper installation is critical to maximizing the benefits of your ERV or HRV system.
- Professional Installation Recommended: While installing an HRV or ERV yourself may seem like a good way to save money, the potential risks outweigh the benefits. Incorrect installation can lead to damage, safety, and performance issues and may void the system's warranty. For almost all systems and situations, we recommend professional installation.
- Location: ERVs and HRVs should be installed in a location with a temperature above freezing and where the fresh air intake is at least 6 feet away from any exhaust sources.
- Integration with Existing Systems: Installing an ERV or HRV may require changes to the existing ductwork to accommodate the new ventilation system.
- Electrical Requirements: Ensure your home has an adequate power supply and the installation complies with electrical codes.
- Accessibility: Install your ERV or HRV in a location that allows easy access for maintenance tasks. Many systems have multiple installation configurations, allowing for different home designs and placement options.
Top ERV and HRV Brands
- Broan: Broan offers a diverse lineup of cutting-edge ERV and HRV systems, with auto-balancing and self-adjusting technology, power, and sizing options to fit nearly any space requirement. Consider the innovative Broan ONE BLP150E75 ERV, which offers a flexible ventilation solution for single-family homes, townhomes, and multi-family developments.
- Fantech: Fantech ERVs and HRVs are comprehensive ventilation tools for even the largest commercial or residential spaces. Their lineup includes models like the Fantech FIT 70E, a low-profile ERV with flexible installation, or the Fantech SHR 800, an HRV that provides powerful ventilating airflows up to 794 CFM.
- S&P: S&P offers a wide range of professional-grade ERVs for residential and commercial spaces. Models like the S&P TR90 and TRe90 Series are known for their easy installation, efficient operation, and versatile power options.
Sylvane's Expert Take
Improving your home's air quality with an ERV or HRV system is a worthwhile investment for your comfort and health. Understanding the differences between these systems is essential in buying the right one. Whether you opt for an ERV or HRV, consulting with experienced professionals can further guide your decision-making, ensuring your home remains as comfortable and energy-efficient as possible.
For more information about ERVs and HRVs and help finding the best device for your home, call Sylvane product experts toll-free at 1-800-934-9194.
