How Long to Run Your Air Purifier: When and How Often to Clean the Air in Your Home

How long to run an air purifier is a question that many people have. How often should you clean the air in your home? How long should you run the air purifier each day to get the indoor air clean? How can you stay energy efficient? Here, we will answer all of these questions!

How Air Purifiers Clean the Air

Air purifiers are a great way to clean the air in your home. An air purifier works by removing dust particles, pollen, pet dander, and other airborne pollutants from the air. But how do they work? And how long does it take for them to work?

Air purifiers work by drawing in dirty air from the room and passing it through a filter. The filter removes the air pollutants and then circulates clean air back into the room. Air purifiers’ speed is rated by the CADR (Clean Air Delivery Rate). The higher the CADR, the faster the air purifier can clean the room.

Most air purifiers have three speed settings: low, medium, and high. The low setting is usually used for small rooms or when you first turn on the air purifier. The medium setting is typically used for medium-sized rooms. The high setting is usually used for large rooms or when the air quality is poor.

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Understanding How Quickly an Air Purifier Can Clean a Room’s Air

The speed at which an air purifier can clean a room’s air depends on the size of the purifier and the room size. A small purifier in a large room will take longer to clean the air than a large purifier in a small room.

Other factors include the air filters, such as a HEPA filter and activated carbon filters, the indoor air quality, and the extraction rate. A HEPA air purifier will remove airborne pollutants better than many other types of air purifiers, but you need to make sure the HEPA filters are not clogged up.

When you run an air purifier, you can sometimes get an idea if you have clean indoor air by an air quality indicator on the purifier.


Most air purifiers have a fan that can be set to different speeds. The higher the fan settings, the more quickly the purifier will clean the indoor air.

The low setting will clean the room slower than the medium or high setting. However, it will use less energy and be quieter.

The medium setting will clean the room faster than the low setting, but it will use more energy and be louder.

The highest setting will clean the room the fastest, but it will use the most energy and be the loudest. You should not use the high setting while you sleep, as it can be very noisy and may keep you up at night, especially if you are a light sleeper. Some air purifiers have a sleep mode that runs the fan at a lower setting to not disturb your sleep while running.

You can use the high setting to quickly remove smoke particles, odors, and other smells. But if you leave your air purifier running on the highest setting all the time, it will use more energy and make higher utility bills.

When to Run Your Air Purifier

There are a few things to consider when deciding when to run your air purifier. You should think about when you will be using the room, how many people will be in the room, and what kind of activity will be going on in the room. Room air gets dirty quickly with use which is why many people run their air purifiers all the time on the low setting.

Should I Keep my Air Purifier Turned on While I’m Out?

You can run your air purifier while you are out, but it is not necessary. The air in your home will not get dirty as quickly when you are not there. If you have pets, you may want to run the air purifier while you are away to remove any pet hair or dander that they may have left behind.

Should I Leave an Air Purifier on While I’m Asleep?

Yes, you should run your air purifier while you sleep. The air in your bedroom can get dirty quickly with use, and purifying it will help you get good quality sleep.

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Can I Run my Air Purifier on a Timer?

You can put some air purifiers on a timer if the model has one. This will allow you to set it to run for a certain amount of time each day. Putting the air purifier on a timer is a good way to stay energy efficient.

What’s the Best Schedule if I Want to Stay Energy-Efficient?

If you want to stay energy-efficient, you should run your air purifier on the low setting when you are home and awake. You can put it on a timer to run for a few hours each day while you are away or asleep.

Some air purifiers have advanced features and are programmable. You can set them to turn off while you’re out of the house and back on a couple of hours before you return. This way, you’re not running the unit unnecessarily and wasting energy.


Air purifiers are a great way to remove dust, pollen, and other allergens from the air. They can also help to remove smoke, odors, and other smells. By running your air purifier on the low setting when you are home and awake, you can stay energy-efficient and always have fresh air. You should now have a good understanding of how long to run your air purifier and when to do so.

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