Informational Guide

Comparing Air Purifiers vs AC Units

We compare air conditioners and air purifiers to see which best suits your needs. See which appliance cools and cleans the air better.

by Josh M

We’re all more health-conscious than ever before and looking to influence the environment around us to support our bodies. Home appliances like air purifiers and air conditioners help control the air around you, but while they have similar functions, there are some key differences.

In this guide, we’ll help explain what an air purifier does and what an air conditioner does so you can better understand the similarities and differences. We’ll give you the full breakdown of air purifiers vs. air conditioners so you can determine which is best suited for your needs.

best air purifier for mold

Air purifiers are designed to remove impurities from the air in your home. They can help neutralize bacteria and pollutants in the air that can have a detrimental impact on your health. They can also remove some particles which trigger asthma or allergies.

Air purifiers are made up of a fan and some filters. The fan is used to draw air into the device, and it then goes through a series of different filters. This removes the larger particles and allows clean air to be blown back into your home. Some air purifiers also use UV light to purify the air, directing a high concentration of UV onto the air as it passes through the purifier. This helps to deactivate certain impurities and leave the air cleaner.

The first air purifier was created in 1963 by a German couple, Manfred and Klaus Hammes. This made use of the High Efficiency Particulate Air Filter, designed in the 1940s to remove bacteria and other harmful particles. Later in 1963, the clean air act was passed in the US, which led to a huge rise in the creation of air purifiers.

Since then, there have been continuous improvements made on air purifiers and the introduction of new technology and features. While the principle has remained the same, the air purifiers we use today are very different from those used in the 1960s.

We take over 20,000 breaths a day, and the majority of these are in your home. Having access to clean, purified air helps protect your lungs and respiratory system, and they can be an asset in any home.

Air purifiers work particularly well for homeowners with allergies who need extra protection from impurities in the air, and those with pets who can bring in a lot of pollutants and allergies themselves. In addition, they have been proven to help prevent illness and can be beneficial for anyone with an underlying health condition.

Pros & Cons of Air Purifiers In the Home

What We Like
  • Removes Harmful Bacteria
  • Relieves Symptoms Of Asthma
  • Relieves Allergies Caused By Pets
  • Can Kill Airborne Diseases
  • Can Help Improve Quality Of Sleep
Things We Don’t
  • Needs Windows Closed To Work
  • Purely Maintained Air Purifiers Can Make Air Quality Worse
  • They Won’t Normally Remove Bad Odors

Overview Of Air Conditioners

Mini Split in Living Room with Grey and White Theme

Air Conditioners are used to help reduce the temperature in your home by removing excess heat and moisture. They allow you to control your home environment by regulating the air and are now found in over 70% of homes across the USA.

The first AC was invented by Willis Carrier in 1902. He discovered that passing dry air through water could create fog and that the moisture levels of the air could be controlled. His initial invention looked to regulate the humidity, which became a blueprint for future models. However, it wasn’t until later in the 20th Century that commercial air conditioners were adopted, and not until the 1960s that home ACs became popular.

There are several different types of modern air conditioners, but they all operate similarly. They tend to have a fan, coolant, and condenser coils. Air is drawn into the device using the fans and directed over the coils, which are filled with coolant. The heat and moisture from the air are drawn out onto the condenser coils, and the dry air is then circulated back into your home. This helps the area around the AC feel a lot cooler.

Portable air conditioners are used in a variety of home settings because they let you plug in and use them immediately. There’s no need for complicated installation, and they can be moved or stored when not in use. If you live in a hotter environment, you may opt for a fitted central air AC which will provide more significant amounts of cooling. These come with a higher cost but can be a good investment. Some other designs, like mini-split air conditioners, are more practical and offer more cooling than portable models.

Air conditioners are beneficial for anyone who lives in a hot, humid area. They help you feel comfortable in your home and better control the environment around you. They’ve been shown to improve the overall air quality and can help to protect your belongings from excess moisture.

Pros & Cons of Portable ACs In the Home

What We Like
  • Keeps You Cool
  • Easy To Move And Store
  • No Installation Costs
  • Perfect For Cooling A Single Area
  • Low Maintenance
Things We Don’t
  • Won’t Cool Your Whole Home
  • Can Be Noisy
  • Expensive Running Costs

Air Purifier vs Air Conditioner: Key Differences Explained

Hopefully you now have a clearer idea of what ACs and air purifiers can do in the home. There are some similarities, but they are very different pieces of equipment. Here’s a quick breakdown of the key differences:

Cooling the Air/Heat Removal

Air conditioners are designed to remove moisture from the air, and in doing so, they make the room cooler. An average portable AC can cool an area of 100-300 feet and produces about 8000 BTUs. An air purifier will have very little impact on the temperature of a room. They filter the air and don’t adjust the temperature, though some people have said that the fan in the purifier can have a mild cooling effect.

If you’re looking to cool the air in a room, then you need an AC.

Humidity Removal

An air conditioner’s primary function is to remove humidity from the air. They do this by forcing the air to flow over condenser coils which allows the moisture to drip away. Air purifiers, on the other hand, offer no humidity removal. The process of filtering the air doesn’t get rid of any moisture, only impurities, so the humidity levels remain fairly constant. If you want to adjust the humidity in a room, you need an AC, not an air purifier.

Air Purification

Air purifiers are designed to filter out any impurities in your air, so they clearly lead in this category. However, air conditioners also come with built-in filters that help to prevent bacteria, pollen, and other contaminants from entering your air stream. Therefore, they do have a positive impact on your air quality, just not to the extent of an air purifier.

best air purifier for allergies
For Allergies

Air purifiers will successfully filter out a lot of contaminants that can trigger allergies. They work well for homeowners who have pets because they can kill and remove the mites which dogs and cats carry. This means they can reduce the chance of your allergy flaring up at home.

Air conditioners, on the other hand, can be bad for allergy sufferers. They draw in air from the outside, and even though it passes through a filter, it can still lead to an increase in the number of mites and other triggers in your home. If you do suffer from allergies, you’ll need a very good filter in your AC.

For Asthma

Asthma can be triggered by a number of different things in the air, including smoke, dust mites, mold, and outdoor pollution. An air purifier will actively work to remove these from your home and should help to alleviate the pressure on asthma sufferers.

Portable air conditioners can help to filter out some of these particles but won’t do it as effectively as an air purifier. However, ACs will reduce the moisture in the air and help to prevent mold buildup. Dry air is better for people with asthma, and there are proven benefits to having an AC in your home. You’ll feel the benefit of an air purifier more, but an AC can also be useful.


COPD is short for Chronic Obstructive Pulmonary Disease, which is a conditioner that limits the amount of air flowing into your lungs. This can lead to fatigue, wheeziness, coughing, and shortness of breath. The best way to regulate this condition is to control the air temperature and humidity.

An air purifier won’t really do this, but it can make it easier to breathe with clean air. An AC will actively let you control the humidity and temperature of the air and support those with COPD. You do have to be careful not to let it get too cold, though, and make sure the humidity stays at around 40% if possible.

For Dust & Pollen Reduction

Portable air conditioners will filter out some larger dust and pollen particles from the air, but they won’t get the finer ones. An air purifier is designed specifically to deal with all the different dust and pollen. If you have hay fever, then you won’t really feel the benefit from an AC, but an air purifier will help.

For Removal of Airborne Contaminants

Other airborne contaminants include germs, bacteria, and microorganisms. Again, an AC will filter some of these out, but others are much too small to be caught on filters. Some air purifiers are specifically designed to deal with these contaminants and even use UV light to deactivate them. This doesn’t remove them from the air but will prevent them from being harmful. If you’re concerned about airborne contaminants, you really need an air purifier, not an AC.

Safety In Bedrooms

Using electrical devices in a bedroom can be risky, but modern portable ACs are perfectly safe. They have anti-tilt technology and built-in safeguards to shut off the device if it stops working properly.

Some people are concerned that an AC can dry out the air too much while you sleep, but medical experts have determined that it can actually be beneficial to leave an AC on so your body is kept at the right temperature all night.

Air purifiers are also perfectly safe to use at night, and most have all the electrical safety precautions that eliminate the risk of an electrical fire. Many air purifiers come with a night mode which reduces the sound and light given off by the device and helps you sleep soundly.

Both ACs and air purifiers can be used safely in bedrooms and left on overnight.

Upfront Costs

For both air purifiers and air conditioners, there’s a lot of variety when it comes to price. You can spend a little or a lot, but you tend to get what you pay for. An air purifier can cost anywhere from $100-$1000 depending on exactly what you need but bear in mind that you’ll need to pay for replacement filters too. Portable ACs also vary in price, but you can get some decent models for under $200. You’ll generally pay less upfront for an AC.

Running Costs

Portable air conditioners and air purifiers generally run from your main electricity. Some modern portable ACs are built to be more efficient, but they generally have high running costs. In comparison, an air purifier will be slightly cheaper, and you’ll spend less to power it. You will have to spend more on filter replacements, but generally, air purifiers are cheaper.

Can Air Purifiers Be Used as Air Conditioners?

This is the key question, really; can you use an air purifier as an AC? The simple answer is no. They are separate appliances and should be used for different functions. You can’t interchange a purifier with an AC and expect to get the same results.

That being said, there are some excellent air conditioners with air purifiers built-in. These give you the best of both worlds and allow you to control the quality, temperature, and humidity of the air in the room. The Dyson HP01 Pure Hot & Cool HEPA Air Purifier is one of the market leaders which combines the purifier and AC functions. Dyson is a company of vacuum specialists, and they integrated that technology to remove even the smallest impurities, and it has a filter that captures 99.7% of allergens.

On top of the air purification, it also has a fan that can provide heating and cooling to a room. It oscillates to have the most impact on a whole room and has 10 different airspeed settings so you can adjust it as needed.

The key benefit of this Dyson air purifier is that it can help you regulate the air temperature and quality in one go. It saves you having two noisy, expensive machines, and gives you efficient operating with a very quiet mechanism. This is the solution for any homeowner who suffers from allergies or asthma and lives in an environment that can get too hot or too cold.

People Also Ask (FAQ)

Do air conditioners bring in the air from the outside?

Many types of AC draw in cool air from the outside and circulate it around your home, but portable air conditioners work without ventilation and don’t actively draw air in from outside.

Can I use an air purifier and air conditioner at the same time in the same room?

You can use both devices at the same time in the same area, but it’s often more efficient and cost-effective to buy one integrated device which fulfills both functions.

What are some reputable brands of portable ACs and purifiers?

Dyson, Honeywell, PurOxygen, Coway, Winix, and Blueair all make good quality portable ACs and purifiers. Always look for HEPA air filters to get the best quality ventilation products.


Both air conditioners and air purifiers are useful appliances, but they can’t be used interchangeably. If you want to remove bacteria, allergens, pollen, and other contaminants from the air, then you need an air purifier. If you want to control the temperature and humidity of a room, then you need an air conditioner. If you decide you need both, then you can get some effective air conditioners with built-in purifiers to give you the benefit of both devices.

Hopefully, this guide has helped explain the two different types of devices and helped you identify what it is you need in your home.

Last Updated on June 29, 2022

Josh M

My name is Josh and I am obsessed with the HVAC industry. I created this website to help HVAC techs of all levels get the best out of their heating & cooling systems. I have spent thousands of hours studying air conditioners, heaters and home air products so you can learn & buy with confidence. Learn more about the team here.