ERV vs. HRV featured photo

We spend most of our time in our homes. Homeowners want the best things for their families, including air quality. One way to ensure this is with air ventilation systems like ERV or HRV.

ERV and HRV systems work practically the same in how they recover heat or chill from outgoing air to incoming air so it’s preheated or precooled. The significant difference is an ERV system can also recover some moisture from the outgoing air. This ensures optimal humidity levels in your family’s indoor air.

Humidity level control isn’t always the best bet, especially if your regional climate doesn’t even need it. There are also several other factors to consider in which system you should get for your home.

In this article, we’ll go over the basics of both ERV and HRV and the common query of ERV vs. HRV. We’ll also lay down what you should consider in choosing the best ventilation system for your home.

Why is Air Ventilation Important?

Everyone wants and needs fresh air in their homes. No one wants to subject their kids and family to dirty, polluted, and contaminated air.

Too many emissions from daily activities, chores, and appliances in the house can make indoor air stuffy. This makes it hard to breathe and can lead to health complications.

When these emissions build up inside the house, it’s not only damaging to people’s health. It can also damage the house’s construction, leading to cracked walls, peeling paint, or worse.

Why Do We Use Air Ventilation Systems?

To prevent this buildup of emissions inside homes, many households use air ventilation systems.

An effective air ventilation system ensures each room in the house gets enough air exchange. This means emissions are exhausted out of the house and a new, fresh air supply is brought in.

Air ventilation systems could be simple exhaust fans or range hood fans. These help exhaust used air out into the world while bringing in a new supply of air.

These are certainly effective and helpful but whole-house ventilation systems take the benefits up a notch. They are able to cover the entire house and supply fresh air to all rooms in your home.

One other benefit these systems offer is they either preheat incoming fresh air in the winter or precool incoming fresh air in the summer, saving your heater and AC unit some intense work.

Two of the most sought-after air ventilation system for many modern homes are HRV and ERV.

HRV and ERV are both fairly new in the house-construction world so it doesn’t come as a surprise that many are confused about what these two are.

We’re here to tell you what HRV and ERV are and how they are both similar and different.

What is HRV?

Heat Recovery Ventilation or HVR is an air ventilating system that vents stale exhaust air outdoors. At the same time, it also draws fresh outdoor air in and distributes it to the rest of the home.

The HRV system ensures you and your family get to breathe fresh air throughout the year, limiting emissions inside your home.

How does it work?

An HVR system has two air ducts. One air duct carries emissions and stale exhaust air out from inside the home. The other air duct carries incoming air inside the home.

Both air ducts pass through a heat exchange system. This transfers heat from the outgoing air to the incoming air. They do so without the two airstreams coming in contact with each other so the new air supply is never contaminated.

As it exchanges stale exhaust air with fresh air supply from outside, the HVR system uses the heat from the outgoing air to pre-heat incoming air.

The same thing happens during the summer months. Instead of exchanging heat, the two airstreams exchange cool air. This exchange pre cools the incoming air thanks to the outgoing air. Again, the two air streams never come in contact.

This hot or cool air exchange (depending on the season) reduces the energy your house heating system and air conditioning system require to keep your home either warm and cozy or cool and breezy.

Benefits of installing HRV

There are tons of benefits an HRV system offers. That’s why many modern homes choose to install one.

  • HRV provides consistently fresh air in your home.
  • An HRV system in your home preheats and pre-cools incoming air. This means your home’s HVAC system reduces the energy it consumes to get your home to optimal temperatures depending on the season. This leads to reduced utility bills in the long run.
  • A whole-house HRV system is not only energy-efficient, but it can also help homeowners reduce their carbon footprint. In the heat exchanger duct, almost 85% of old heat is reused for the incoming air so the heating system uses far less energy.
  • HRVs come with pre-built-in filters that restrict the entry of insects, contaminants, dirt, and pollution into your home.

What is ERV?

Another sought-after ventilating system in most modern homes is the ERV.

ERV stands for Energy Recovery Ventilation.

ERV is pretty similar to HRV in the way it vents used, stale air into the outdoors while at the same time drawing new, fresh air from outside to distribute to your home. What sets it apart from HRV is while it manages the temperature of the air that you breathe, it also manages humidity.

EVRs not only ensure your family breathes in clean, fresh air but also lives in an environment with just the right humidity level for the season.

How does it work?

As mentioned above, the way ERV works is similar to an HRV.

ERVs have two air ducts – one air duct to carry stale exhaust air from inside the home to the outside and another to carry fresh air supply back into the house.

When these two airstreams meet at the heat exchanger, some of that heat or chill from the exhaust air transfers to the incoming fresh air supply.

Depending on the season, this preheats or pre-cools incoming air so your HVAC system doesn’t work as much as it would without it.

Aside from the temperature, an ERV system can also retain humidity from the air inside your home. In doing so, it ensures your home and family stay at a comfortable humidity level (which is usually at 40% to 60%).

The system either removes humidity from the incoming air or retains humidity from the outgoing air and transfers it to the fresh supply of incoming air.

Like HRV, the two airstreams in an ERV system don’t come in contact with each other so the incoming air isn’t at all contaminated by the outgoing air.

An ERV system ensures the air in your home isn’t too humid or too dry, eliminating possibilities of mold, mildew, sore throats, dry skin, or condensation on the windows.

Benefits of installing ERV

A whole-house ERV system presents many benefits across many households in the US:

  • ERV always provides clean, fresh air into your home.
  • ERVs not only maintain optimal temperatures of the air inside your home but also maintain optimal humidity levels. This helps prevent the growth of molds and mildew, while also preventing sore throats and dry skin in members of your household.
  • An ERV system is able to either preheat or precool incoming air, effectively reducing energy consumption. Installing one right in your home helps you chunk huge amounts from your utility bills.
  • ERVs come with air filters that filter out dirt, pollution, insects, and contaminants and prevent them from entering your home.

How are ERV and HRV Common?

Now that we’ve gone into detail about what ERV and HRV both are, let’s go over what their similarities are and what makes them common.

  • Both ERV and HRV systems consistently discard exhaust air from inside the house and bring in a fresh supply of air from outdoors.
  • Before reaching their destination, both ERVs and HRVs either preheat or precool incoming hair thanks to the outgoing air.
  • ERV and HRV systems get rid of stuffy air from inside the house.
  • Both systems are able to distribute air from all rooms in the house (typically except the garage).
  • ERV and HRV systems have the means to filter the air coming inside the house so no pollution, dirt, and other contaminants make it into your family’s breathing space.

ERV vs. HRV: What’s the Difference?

ERV and HRV systems work practically the same. The only significant difference is this: moisture recovery.

While both an ERV and an HRV retain and recover some heat or chill from the outgoing air to the incoming air, only the former retains and recovers moisture as well.

Being able to do so is important to prevent indoor air from getting either too dry or too moist. Both extremes can be harmful to both the construction of your home and your family.

Dry air can cause sore throats and dry skin. Too humid and moist air can make your home susceptible to mold and mildew growth, which can lead to respiratory issues and allergies.

When Do You Need an HRV for HVAC?

An HRV system is a good default choice for many homes. It’s especially a great choice if you live in a region that doesn’t particularly experience extremely dry seasons, whether it’s warm or cold.

When Do You Need an ERV for HVAC?

On the other hand, you might want to consider going for an ERV system if you experience extreme humidity levels.

Summers and winters can either be too humid or too dry, depending on where you live. If you experience both extremes as the season changes, the ERV might be a better choice as it can retain and control moisture levels in your home’s indoor air as well.

You might also want to read: Are ERVs Worth the Money?

HRV vs. ERV: Which is the Better Choice?

There are several factors to consider when making the choice between an HRV or an ERV:

  • The number of people in your home: Larger families accumulate more moisture and humidity from daily activities like cooking, washing clothes, and breathing. An HRV system would fit these families well. On the other hand, the fewer people in your home, the drier the air will be. To retain some of the humidity, the ERV is the better choice.
  • The size of your home: For homes that are small to medium in size that accumulate humidity quicker, HRVs are recommended. For bigger homes that tend to have drier air, ERVs are the better choice.
  • The sealing of the home: The more airtight and sealed the home is, the more moisture remains inside. For homes that fall into this category, HRVs are a good choice. For homes with drafts where moisture tends to escape, an ERV system will help keep humidity at safe levels.
  • Your home’s heating system: Home-heating systems like a boiler don’t dry out indoor air so an HRV will work well. Heating systems like heating with wood can dry out indoor air so an ERV might fare better. 
  • Regional climate: Lastly, the regional climate where you live should play an important role in the choice between HRV and ERV. Generally, those who experience only humid air will do well with an HRV. And if you want to get rid of excess humidity, a dehumidifier will do. Those who experience both extremes of too-humid and too-dry indoor air can significantly benefit from an ERV.

HRV vs. ERV for warm climate

For warm and humid climates, the HRV is a better choice. On the other hand, warm and dry summers can fare better with an ERV system in place.

HRV vs. ERV for cold climate

Dry and cold winters can achieve better indoor air results with an ERV while cold and humid winters will do fine with an HRV system.


Indoor air quality is a very important factor for many homeowners. After all, it’s the space we live in and the air we breathe in. Air ventilation systems are important factors to look into to make homes comfortable and two popular systems are the ERV and HRV.

Both work similarly, but ERVs also recover some moisture so indoor air is also at its optimal humidity level.

Please don’t hesitate to reach out to us if you have more questions!

Related Articles

Well Water vs City Water featured image

Well Water vs City Water

Everyone needs water for drinking, cooking, bathing, cleaning, and more. If you’re a homeowner, then you are probably in the middle of deciding between well water vs

Read More »