What Is An ERV System?

What Is An ERV System featured photo

Part of guaranteeing your family’s health is through the air in your living spaces. After all, it’s where we spend most of our days. Many homeowners have taken the initiative to install air ventilation systems like ERV. In this post, we’ll explain what an ERV system is and what one does. 

An Energy Recovery Ventilator, or ERV, is an air ventilation system that ensures quality fresh air makes it inside regularly. It does so in two steps: by exhausting stale indoor air and drawing in fresh outdoor air. This happens at the same time as recovering and transferring both heat energy and moisture from the outgoing air to the incoming air.

How an ERV works would depend on how it was installed with your HVAC system, what your home requires, and the current season.

Below, we’ll go into detail on what an ERV system exactly is and how it works. We’ll also help you decide whether this is for you or not by talking about all the good and the bad that comes with it.

Proper Air Ventilation and Why It’s Important

Today’s modern homes are as airtight and sealed as they can be. Unlike those constructed decades ago, today’s buildings aren’t as drafty, making them more energy-efficient.

Airtight construction means there’s no draft, getting rid of the chance of heat escaping and the cold creeping its way in. This also means they are far better equipped to maintain optimal living temperatures, whether it’s winter or summer.

Though this is good news in more ways than one, it’s not all good news.

Airtight and sealed homes could also mean indoor air can be stuffy with excess moisture. Daily activities like cooking, washing and drying clothes, taking baths and showers, and breathing accumulate emissions.

This can be an uncomfortable breathing space. On top of that, used stale air is dirty and contaminated. A combination of these two could lead to an array of respiratory problems.

We also need continuous air exchange to ensure healthy air, especially indoors.

What is an ERV System?

This is what an ERV, or an Energy Recovery Ventilator, helps with.

An ERV is a modern air ventilator system in many homes across the country. What it does is prevent this unwanted build-up of emissions and ensure clean and quality indoor air.

Of course, cracking open a few windows throughout the day can help with that but that will also allow cold or hot air into your home. You might as well be throwing money on heating and AC bills every time you crack open a window to let fresh air in.

An ERV ensures clean indoor air by exhausting used, stale air from inside to the outside. At the same time, it draws in a fresh supply of outdoor air and brings it indoors. This cycle ensures a new supply of fresh air and distributes it to the rest of the house or any building.

As it vents out the used and stale indoor air, it also retains and recovers some of the heat and moisture from the outgoing air and transfers it to the incoming air.

In the winter, this preheats incoming air and ensures there is a stable level of humidity indoors. In the summer, the cycle precools air and prevents excess humidity inside your home.

ERV in HVAC systems

Your ERV system is meant to be connected and installed with your home’s HVAC (heating, ventilation, and air conditioning) system.

It works with your home’s HVAC to ensure a continuous cycle of air exchange.

An ERV installed right in your home can help your heating, ventilation, and air conditioner units do a more efficient and better job.

How Does an ERV System Work?

An ERV system has two air ducts so there are two air streams. One air duct is for venting and exhausting stale used indoor air. The other draws in a new supply of fresh air from outside.

These two separate air streams pass by the heat exchanger (sometimes called the air exchanger) at the ERV’s core but they don’t ever come in contact. When they pass through this heat exchanger, some of the heat from the outgoing air is retained and transferred over to the incoming air, preheating it.

During summer, it retains and transfers the chill and cold from the outgoing air to the incoming air, which precools the air.

At both times (depending on the season), an ERV system helps with the efficiency and performance of your home’s heater or AC unit so they don’t have to work as hard.

Aside from maintaining optimal living temperatures indoors, an ERV system is also capable of retaining moisture and humidity when needed. This works best for especially cold and dry winters to prevent too dry indoor air.

During humid summers, on the other hand, this function helps remove excess humidity from incoming air. This function also helps with your dehumidifier’s efficiency rate.

It’s important to note that ERVs are not dehumidifiers. What they do to prevent excess humidity is prevent their entry into your home. They do this by taking the humidity from incoming air and transferring it to the outgoing air.

Learn more about sizing an ERV system for your HVAC.

Do I Need an ERV System?

ERV systems are generally a convenient addition to many homes.

As a general consensus, ERVs will do wonders for those who live in humid climates as it’s able to keep excess moisture and humidity from the outdoor air outside.

But of course, that isn’t the only thing you should factor in.

To help you decide whether an ERV is right for your home and your family’s needs, we’ll detail below all the good and the bad of an ERV system.

What are the Benefits of Installing an ERV?

Improves indoor air quality

An ERV system in place makes sure you and your family constantly get a supply of new and fresh indoor air. With an ERV, the air you breathe in is well-ventilated, clean, fresh, and free from toxins and contaminants.

ERVs can also flush out pollutants, dirt, dust, pollen, and other allergens that might be a risk to your family’s health.

Healthy and clean air means a healthy family.

Controls humidity levels

An ERV in your home’s HVAC system provides needed ventilation. This gets rid of all that moisture, emission, and humidity build-up that makes your family’s breathing air stuffy and uncomfortable.

While it can get rid of excess humidity along with the air exchange process, it also works to keep and retain moisture whenever needed.

If you don’t already know, both humidity extremes (too moist and too dry air) can have unpleasant results.

Air that’s too dry can cause sore throats and dry skin. Too moist air, on the other hand, is a breeding ground for molds and mildew.

Improves HVAC efficiency and performance

ERVs either preheat or precool incoming air. This means it takes a huge load off your HVAC’s back. With an ERV, your home’s heating and air conditioning won’t need to work as hard, making it more efficient than ever.

Air filtration

ERVs come with built-in filtration systems. These filter out dirt, dust, insects, pollutants, pollen, and other allergens that can heighten allergies and respiratory issues.


Many manufacturers claim that their ERV systems can retain up to 99% of energy from outgoing air. Preheating or precooling incoming air can lead to a reduction in your energy and utility bills. This can help you save more in the long run.

Ventilation and odor control

Say goodbye to having to throw money out the window whenever you open one to ventilate your home. An ERV system ventilates for you.

ERVs also help control and eliminate odor from pets, smoke, and other foul-smelling materials.

Easy maintenance

ERVs are fairly easy to maintain and require very little attention. All you need to keep in mind is to change the filter every few months and have the unit regularly checked by a technician.

What are the Drawbacks of Installing an ERV?

High initial cost

ERV units and their installation do not come cheap.

The unit itself and having it professionally installed can generally cost you $2,000 or more. Of course, this price can go lower or higher depending on a variety of other factors.

Read more on how much ERVs cost here.

Electric usage

ERV systems run on electricity. Having it run all year, you can definitely see it adding up to your electricity bills.

How it helps save on utility bills, as we’ve mentioned, would depend on your personal usage and how it was installed to work with your home’s HVAC system.


ERVs work to vent out used air and draw in outside air. This produces a lot of noise. This might cause some annoyance if you have yours running all day.

To avoid discomfort, it’s highly suggested to install it somewhere the noise won’t bother any of the occupants.


In the many discussions about ERV systems, HRV is almost always part of the conversation.

HRV, or Heat Recovery Ventilator, works practically the same as an ERV.

The only difference is HRVs only retain and transfer heat or chill from the outgoing air to the incoming air, whereas ERVs can do both heat energy and humidity.

For a deeper dive into the similarities and differences between an ERV and an HRV, head over to our detailed guide here.


All homeowners want the best for their families, and this obviously includes their health. One way to make sure your family’s health is to make sure they only breathe clean and quality indoor air. One way to ensure this is with an air ventilator system like the ERV.

An ERV, or Energy Recovery Ventilator, is an air ventilator system that prevents the build-up of emissions and moisture inside homes and buildings, ensuring clean, fresh, and quality indoor air. What it does is vent out stale air and draw in a new supply of fresh air.

And that has been our detailed guide on everything about ERVs. For other questions, you can contact us below!

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