What’s the Difference Between A Home Air Exchanger & Purifier?

Many of our customers ask, “Do I need an air exchanger in my house?” To answer that question, let’s discuss what an air exchanger is, and how it’s different from an air purifier. If you’re noticing quality issues with your indoor air, it’s likely that you’ll need one of these systems.

Interestingly, many homes these days have issues with indoor air quality because of how tightly they’re built. Improved technology in windows and insulation makes it very hard for air to pass through, keeping the air in your home from circulating.

Air Exchangers

An air exchanger is a ventilation system for the whole house. It removes stale or polluted indoor air and replaces it with fresh air from outside, helping to promote good indoor air quality. Air exchangers work by using a central air exchange unit, responsible for circulating the air, and a system of ducts within your walls to let the air travel. Some of these ducts expel the old air out of the house, while others bring in new air from the outside, distributing it to various rooms throughout your home. There are filters built into the air exchange unit, helping the system remove dust, pollen, and other airborne particles.

Generally, humid air and pollutants linger toward the top of houses, sitting stagnant within the highest rooms. A good air exchange system should extend to the upper level of the house and all of the most important rooms, including kitchens and bathrooms, where air quality can be impacted by humidity and odors.

Generally, any rooms containing air exchange ducts will also contain control panels, allowing you to turn the system on for a set period of time. When the system is activated, it works throughout the entire home, not just the room you’re in. So, if you turn on the air exchanger in the upstairs bathroom, for instance, it will begin to circulate air to the downstairs kitchen, bathrooms, or any other room included in the system.

Air Purifiers

Air purifiers are also meant to improve indoor air quality, but instead of being built into your house, they’re usually smaller – often portable – contained units.

Since these units have no duct work, they don’t exchange indoor air for outdoor air. Instead, they work by taking in air, purifying it, and releasing it back into the room. Some of these systems use filters, while others use UV light, ion technology, and more. Let’s look at some of the different air purifiers available on the market:

HEPA Air Purifiers

•HEPA, or high-efficiency particulate absorbing, air filters can absorb up to 99.7% of all particles larger than 0.2 microns, such as dander, dust, mold, and pollen. Due to their efficiency and ability to remove common airborne contaminants, HEPA air purifiers are fairly popular and a common choice for people looking to cleanse their indoor air.

Ultraviolet Air Purifiers

• Ultraviolet, or UV, air purifiers were invented to mimic the sanitary practices of hospitals, where UV light is used to disinfect patient rooms and laboratories. The ultraviolet light kills potentially harmful bacteria, viruses, and pathogens. Home air purifiers are very compact, and work by drawing household air into a chamber filled with UV light.

Activated Carbon Air Purifiers

•These air purifiers specialize in one thing: removing odors, gasses, and chemical smells from your home. If you’re sensitive to smoke or fumes, activated carbon air purifiers may be a good choice for you. Unfortunately, since they’re so specialized, they’re less effective at removing dander, dust, mold, and pollen – unless they’re equipped with a HEPA filter.

Ionic Air Purifiers

•Operating without a motor, ionic air purifiers run very quietly. They work by emitting negative ions into the air, which seek out and bond with positively charged particles like allergens, viruses, bacteria, dust, and dander. Once bonded, these airborne contaminants become too heavy to float and fall to the ground.

Air Exchangers vs. Air Purifiers

While air exchangers and air purifiers both remove airborne contaminants, they work in very different ways. Air exchangers are built into the home, with a ventilation system to remove and replace large quantities of air throughout your house. Air purifiers, on the other hand, don’t actually remove or replace any air, but rather treat the air in a given space.

So, is an air exchanger better than an air purifier? If you’re trying to introduce fresh air into your house, nothing matches what an air exchange system can do. But, if you’re only concerned about removing airborne contaminants, then perhaps a cheaper, less permanent air purifier will work for you.

When it comes to your investment in air quality, it’s important to consider not only the initial cost, but the lifespan of air exchangers versus air purifiers. Air exchangers are quite durable, and can easily last 15-20 years. With proper maintenance, it’s possible for air exchange units to last as long as 25 years. When the time does come to replace your air exchanger, you’ll only have to replace the unit itself. The ductwork in place, a large part of the system’s initial cost, should last as long as your house does.

While varying technology makes it difficult to accurately gauge the lifespan of air purifiers, they generally last between two and five years, with some systems lasting up to seven years. The relatively low life expectancy of air purifiers aligns with their lower cost, ranging from $50 to nearly $1,000.

The price of an air exchange system largely depends on your home. To find out what an air exchanger would cost you, reach out to the experts at Sedgwick Heating, who will happily provide a no-obligation quote for your custom air exchange system.

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