ERV vs HRV: Which Ventilation System Makes Sense in Sacramento

Modern homes tend to be tightly sealed. While this is great for your energy efficiency, it can trap stale air, moisture, foul odors, allergens, and indoor pollutants inside. Heat recovery ventilator (HRV) and energy recovery ventilator (ERV) systems are designed to bring in fresh outdoor air while exhausting stale indoor air. 

Choosing the right system depends on your goals as well as your location. In Sacramento, homeowners have to take into consideration our hot, dry summers and cooler, wet winters. Energy-efficiency goals, pollen, and wildfire smoke can also impact which decision makes sense for your home. By getting a full indoor air quality (IAQ) evaluation from Fox Family Heating & Air Conditioning, you can discover which type of system works best for your home. 

Why Sacramento Homes Need Better Ventilation

Airtight construction might lower your energy costs, but it can limit the amount of fresh air that gets into your home. While opening windows is sometimes an option, it isn’t always practical during periods of extreme heat, poor air quality, high pollen counts, or intense wildfire smoke. Through balanced ventilation systems, homeowners can receive more controlled fresh air than relying on open windows or random air leaks.

What Is an HRV System?

Known as a heat recovery ventilator, this system is made to transfer heat from outgoing stale air to incoming fresh air. Unlike an ERV system, an HRV isn’t designed to transfer moisture between the two airstreams. It works best for homes that have excess indoor humidity, window condensation, and musty air. In particular, an HRV system is ideal for homes where moisture removal is more important than moisture balance. 

What Is an ERV System?

An ERV system, also called an energy recovery ventilator, transfers heat and moisture between air streams. This means it is an effective option if you’re trying to maintain a balanced indoor humidity level. ERV systems work best in homes that feel too dry during parts of the year or tightly sealed homes that require fresh air without significant energy loss. Additionally, ERV systems tend to be the best choice for families that want balanced humidity and comfort levels throughout the year.

ERV vs. HRV: Key Differences

To get a better understanding of the differences between ERV and HRV systems, check out the following breakdown of each system.

Which System Makes More Sense in Sacramento?

In Sacramento’s climate, there isn’t a one-size-fits-all approach to choosing HRV and ERV systems. Many local homes may benefit from an ERV because it moderates moisture transfer while providing energy-efficient ventilation. However, HRVs are a great option if your home regularly has condensation, excess indoor moisture, or stale, damp air.

Fox Family Heating & Air can perform a full evaluation to determine which system makes the most sense. The right answer will depend on your home’s insulation, ductwork, humidity levels, occupancy, air sealing, and IAQ concerns.

Sacramento Climate Factors To Consider

When deciding which system is right for your home, it helps to consider our local climate and air quality concerns.

Hot, Dry Summers

When the weather warms up in the summer, fresh outdoor air can end up adding to the heat load in your home if ventilation isn’t managed efficiently. With ERVs, you can lower some of the energy costs associated with bringing in outdoor air.

Cool, Wetter Winters

During cooler winter weather, some tightly sealed homes may experience indoor humidity buildup and condensation, depending on ventilation, occupancy, and indoor moisture sources. Stale, humid air is also more prone to musty odors. In homes with excess indoor moisture, an HRV may be a good option because it exhausts humid indoor air without transferring that moisture back to the incoming airstream.

Wildfire Smoke and Poor Air Quality Days

ERVs and HRVs are ventilation systems and not standalone air purifiers, so you may need to limit your outdoor air intake during smoke events. To maintain your home’s IAQ, you may need to rely on increased filtration. A portable air cleaner or MERV 13 HVAC filter can be effective at removing smoke particles from indoor air. However, you should make sure your heating, ventilation, and air conditioning (HVAC) system can accommodate a MERV 13 filter before upgrading.

Signs Your Home May Need an ERV or HRV

You may need to invest in an ERV or HRV if you notice any of the following symptoms.

• Stale or stuffy indoor air
• Musty odors
• Window condensation
• Lingering cooking or cleaning smells
• High indoor humidity levels
• Excessively dry indoor air
• Allergy or asthma irritation when indoors

Additionally, it’s important to have your home evaluated if your property is relatively new. Often, new homes have tightly sealed building envelopes and limited natural airflow, increasing the importance of ERVs and HRVs.

What ERVs and HRVs Do Not Fix by Themselves

While there are many advantages to having an ERV or HRV, these systems cannot fix every HVAC problem. If you’re dealing with mold, dirty ductwork, or inadequate filtration, these systems won’t correct the underlying problem. For instance, reducing wildfire-smoke particles indoors typically requires high-efficiency filtration, such as a MERV 13 filter or an air purifier.

Similarly, the best solution to undersized or oversized HVAC equipment is to replace it with an appropriately sized unit. You’ll also need to find a different solution if you’re dealing with excess humidity from plumbing leaks or crawlspace moisture.

Installation and Sizing Matter

For the best results, you can’t simply install any ventilation system. The new system must be correctly sized for your home and integrated into your HVAC system or ductwork. If it is installed incorrectly, you may notice extra noise, wasted energy, comfort problems, and pressure issues. Before choosing any system, it’s always important to schedule a professional IAQ evaluation.

Questions To Ask an HVAC Professional

If you’re considering an ERV or HRV system for your home, it helps to understand all of the factors involved. Make sure to ask the following questions as you begin the process.

• Is my home tight enough to require mechanical ventilation? 
• Would it make more sense to have an ERV or HRV for my home and Sacramento’s climate?
• Is my indoor air excessively dry, humid, or stale?
• What filtration type makes the most sense during wildfire season? 
• How often will the system need to be maintained?
• Can my existing HVAC system support the added ventilation?

FAQs

Is an ERV or HRV better for Sacramento homes?

Both systems can be used effectively in Sacramento, and the right choice can vary based on the home. With that said, many Sacramento homes will benefit from having an ERV. Because an ERV transfers some moisture between incoming and outgoing airstreams, it can moderate the humidity effects of bringing outdoor air into the home.

Does an ERV dehumidify the house?

No. An ERV isn’t a dehumidifier. It transfers some moisture between the incoming and outgoing airstreams, generally moving moisture from the more humid air toward the drier air. Because this system is still not perfect, some humidity can still be brought inside on humid days.

Does an HRV make indoor air too dry?

An HRV can contribute to dry indoor air when the incoming outdoor air contains substantially less moisture than the indoor air. During Sacramento’s humid days, this is less of an issue.

Can an ERV or HRV help with wildfire smoke?

An ERV or HRV isn’t designed to remove wildfire smoke by itself, and bringing in outdoor air during a smoke event can introduce smoke particles into the home. To protect your family from wildfire smoke, it’s a good idea to talk to one of our HVAC technicians about upgrading your filtration system, installing a whole-home purifier, or changing your ERV and HRV use during smoke events.

Do older homes need balanced ventilation?

Because older homes aren’t as tight as modern buildings, air is naturally exchanged through leaks in the building’s envelope. However, you may need balanced ventilation after a major retrofit or if you have ongoing IAQ issues.

How often should ERV or HRV filters be cleaned?

It depends on the manufacturer, IAQ conditions, and your usage. Often, these filters should be cleaned every one to two months if they are washable. For disposable filters, a replacement schedule ranging between two and three months is fairly common.

Upgrade Your Home’s Comfort

While ERVs and HRVs both improve fresh-air exchange, how they handle moisture is different. For many Sacramento homeowners, an ERV is generally a strong first option for achieving year-round comfort. If excess indoor moisture is an issue, an HRV may be a better choice.

Book an evaluation with a Sacramento IAQ professional today to find out which equipment makes sense for your ventilation, humidity, filtration, and system compatibility goals.