Informational Guide

How To Use An Air Purifier For The Best Performance

by Josh M

Dealing with allergies or congestion from pet dander, pollen, smoke, or other substances is no fun. However, using an air purifier in your home can help.

The purpose of an air purifier is to clean a room of pollutants so that you can breathe easier, but it’s all too easy to run one ineffectively.

If you’re wondering how to use an air purifier, read on. Below we provide the top tips on using an air purifier successfully!

1. Don’t Block Air Circulation

Air purifiers are only effective when they can turn over all the air in a room. To do this, they need plenty of space around their vents. So don’t place an air purifier within six inches of a wall or piece of furniture.

You might be wondering whether your air purifier should be on the floor or not. Though that might be the most convenient place to put an air purifier, it won’t work as well there.

Alternatively, you might wonder if you can put your air purifier on a table. The answer is yes, you can, and you should, especially if you’re running your home’s heater.

Warm air rises and carries pollutants with it. That means your air purifier will catch the most pollutants by being elevated. So, when deciding whether to put your air purifier on the floor or a table, the table is always best.

Finally, you might ask which way an air purifier should face, and the answer is towards the center or widest portion of the room. This allows for the best air circulation.

Where to Place an Air Purifier

2. Keep The Doors And Windows Closed

If you use your air purifier with the window open, your air purifier won’t be as effective. The same goes for the doors in your home.

Air purifiers come in different sizes, but even larger ones can typically only clean 1500 square feet at a time. Opening a window or door greatly increases the amount of air the purifier has to try and clean.

So, it’s best to use an air purifier with the door closed, and the same goes for windows.

3. Leave The Purifier On When You’re In

Air purifiers are most effective when you leave them running. So, if you’re home, they should be on.

Many air purifiers have auto modes that run at a low speed 24/7. Some will even turn off for periods if they sense the air is clean and turn back on if they sense pollutants. This makes them very energy efficient.

If the sound of the air purifier bothers you while you’re trying to sleep, try keeping it on its lowest setting. Usually, the low setting is near silent.

4. Maintain The Filters Regularly

The filters on your air purifier become less effective at catching pollutants as they fill. So, it’s crucial to clean or change your air filters regularly.

Some purifiers come with washable filters that you can rinse and reuse. Others have replaceable filters you’ll need to purchase.

Your air purifier’s manual will tell you how often to change the filters in most cases. Many machines also have an indicator light or sensor to let you know when the filter is full.

5. Clean The Dust Sensor Lens

Some air purifiers have a laser dust sensor that counts the dust particles in the air. To get an accurate reading, the sensor lens needs to be clean.

Ideally, you’ll clean the dust sensor lens about once a month. However, there are certain times, like allergy season, when cleaning it twice a month is a good idea.

6. Don’t Get The Air Purifier Wet

Many people ask if they should put water in an air purifier, and the answer is no. Air purifiers don’t require water to work.

In fact, water is a problem for most air purifiers, and you should avoid putting them in spaces with high humidity. In high humidity, your air purifier’s filter could grow mold, making it ineffective and a possible health hazard.

7. Don’t Put The Air Purifier Near Any Devices

Don’t put your air purifier next to a humidifier or dehumidifier, as they’ll compete for the same air and render both devices less effective. Plus, in the case of a humidifier, you run the risk of promoting mold growth on your purifier’s filter.

Many people ask if they can use a fan with an air purifier, presumably to help push air through the purifier. The answer there is also no.

Running an air purifier and a fan simultaneously seems like a good idea, but you risk overwhelming the air purifier. Pushing pet dander, pollen, and other pollutants through the air purifier faster won’t make it more effective. Instead, more pollutants are likely to get past the air purifier’s filter.

Do Air Purifiers Work With Windows Open?

If you run an air purifier with the window open, the purifier will still work, but it won’t be as effective.

What Happens If You Run An Air Purifier With Open Windows?

If you’re wondering how to use an air purifier with open windows, the answer is don’t, unless absolutely necessary.

When windows are open, allergens and other contaminants float freely into the room. So, there’s a constant flow of pollutants working against the air purifier, and the purification process will take far longer.

Can I Put It On A Table Near A Window?

You certainly can put your air purifier on a table near a window, but you should keep the window closed. If you plan on opening the windows, you might as well turn off the air purifier.

Air Purifier in the Living Room

People Also Ask (FAQ)

Below are frequently asked questions on using air purifiers.

How long does it take for an air purifier to clean a room?

How long it takes an air purifier to clean a room depends on the size of the room and the size of the air purifier. In general, a small room takes about thirty minutes. Larger rooms could take several hours.

Can I move my air purifier from room to room?

Absolutely, you can move your air purifier from room to room as needed.

Related Article – How Many Air Purifiers Do I Need?

What speed should I run my air purifier?

Most people run their air purifier on its auto setting, which will adjust to the best speed given the number of pollutants in the air. If you don’t have an auto setting, consider running it on high speed initially, then turning it to low speed once the air is clean.


If you’re wondering when to use an air purifier, the answer is: use one whenever you need to breathe a little easier!

Air purifier uses range from dealing with pet dander to cleaning a stinky room. As long as you use yours effectively, by following the tips above, you’ll have consistently fresh, clean air in your home.

Last Updated on January 9, 2023

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.