Energy Recovery Ventilators (ERVs) are becoming increasingly common in modern homes, especially in well-sealed, energy-efficient construction. While ERVs are excellent tools for improving indoor air quality and ventilation, they must be used correctly to prevent humidity problems and temperature imbalances.
At Advanced Air Duct Cleaning, we frequently educate homeowners on how their ventilation systems interact with their HVAC systems. Understanding how your ERV works can help protect your home’s comfort and indoor air quality.
What Is an ERV?
An Energy Recovery Ventilator (ERV) is a mechanical ventilation system designed to bring fresh outdoor air into your home while exhausting stale indoor air. Unlike simply opening a window, an ERV transfers energy between the outgoing and incoming air streams.
In the summer, it helps pre-condition incoming hot, humid air by transferring some of the heat and moisture to the outgoing air. In the winter, it helps retain warmth and humidity from the indoor air before exhausting it outside.
How an ERV Works
An ERV contains a heat exchange core where outgoing indoor air passes alongside incoming fresh outdoor air. The two air streams do not mix, but energy (heat and some moisture) is transferred between them.
This process allows your home to receive fresh air that is partially tempered before entering your duct system, reducing strain on your heating and cooling equipment.
Benefits of an ERV
- Improves indoor air quality by introducing fresh air
- Reduces buildup of stale air, odors, and indoor pollutants
- Helps manage humidity levels when operating properly
- Supports energy efficiency in tightly sealed homes
- Reduces strain on HVAC systems compared to uncontrolled ventilation
For homes with pets, larger families, or limited natural ventilation, an ERV can be a valuable component of maintaining healthy indoor air.
What NOT To Do With an ERV
One of the most common mistakes homeowners make is running their HVAC system on ‘Fan’ or ‘Circulate’ mode continuously while operating an ERV.
When you set your system to continuous fan during the middle of summer or winter, air is pulled into the home and circulated through the duct system without being actively cooled, dehumidified, or heated by the HVAC equipment.
In the summer, this can introduce humid air that is not being properly dehumidified prior to distribution throughout your home. This may lead to elevated indoor humidity levels, musty odors, and potential moisture issues.
In the winter, continuously circulating air without active heating can cause temperature imbalances and drafts, making certain rooms feel colder than others.
Your ERV is designed to pre-condition incoming air — but it is not a replacement for your air conditioner or furnace. Improper fan settings can disrupt the balance of your system and create comfort issues.
Best Practices for ERV Operation
- Follow manufacturer guidelines for operation and settings
- Avoid running HVAC fan mode continuously unless advised by a licensed professional
- Schedule regular HVAC and duct maintenance
- Have your ERV inspected periodically to ensure proper airflow and balance
- Monitor indoor humidity levels, especially during peak summer and winter months
Protecting Your Comfort and Air Quality
An ERV is a powerful tool for improving indoor air quality when installed and operated correctly. However, improper settings — especially continuous fan operation, can unintentionally introduce humidity and temperature control challenges.
If you are unsure whether your ERV and HVAC system are working together properly, Advanced Air Duct Cleaning can help evaluate your duct system and airflow to ensure your home remains balanced, comfortable, and healthy year-round, contact us today!