Answers To How Long To Run Air Purifier For And Related Questions

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Air purifiers are great at getting things out of the air that affect our health. Should we run them all the time though? What’s the answer when it comes to how long to run an air purifier for?

Air purifiers should run all day. They can run for shorter periods, but they’re at their most effective when they run all day. This may increase your electric bill, but there’s a way to figure that out, and it’s safe to do.

Questions And Answers: How Long To Run Air Purifiers?

An air purifier sitting on a nightstand by a plant.

What Do Air Purifiers Do?

Air purifiers usually use a fan to draw in the air around them. Something inside, usually one or more filters, trap pollutants in the air while the air goes back into the room. This process lowers indoor air pollution and betters people’s health.

The 6 Factors That Affect Air Purifier Runtime

First of all, most air purifiers can clean a room in between 30 minutes and 2 hours. This is just an average though. Several factors increase or decrease how long an air purifier takes to clean a room.

1. The Type Of Filter And How Many

The more filters an air purifier has the more difficult it will be for air to get through. Also, if a filter has a higher Minimum Efficiency Reporting Value or MERV rating, that can make it more difficult for air to get through.

Also, running an air purifier for longer amounts of time will mean you have to change the filters more frequently, so keep this in mind if you plan to do so.

Learn more about the different types of air purifiers.

2. How Big The Air Purifier Is

Bigger air purifiers can take in more air, which allows them to clean rooms faster than smaller air purifiers.

3. How Big The Room Is

The bigger a room is the bigger an air purifier you’ll need to clean its air. Not getting a bigger air purifier means it’ll take longer to clean the room’s air. If the air purifier is too small it may not be able to clean all the room’s air anyway. Check out the product information to see how big of a room the air purifier is rated to clean.

4. Air Purifier Settings

Most air purifiers come with settings such as sound, light, and also fan speed. Fan speed determines how fast the air purifier’s fan spins, which determines how much air moves through the air purifier. The faster the fan, the more air it draws in, which means the less time an air purifier needs to run.

5. Clean Air Delivery Rate (CADR)

Fan speed is one part of what affects the clean air delivery rate (CADR) of an air purifier. A CADR is how well an air purifier removes particles from the air going through it. The other things that affect CADR are the size of the air purifier, the quality of filters it’s using, and how many particles are in the air.

How To Calculate

The easiest way to figure out CADR is to look at the product information for the air purifier. If the CADR isn’t included, figure out how many cubic feet per minute the air purifier takes in and multiply that by the percent of particles it’s supposed to take out of the air. That gives you the CADR.

6. Air Changes Per Hour (ACH)

While CADR refers to how well an air purifier is cleaning the air, air changes per hour or ACH measures how many times per hour all the air in a room is replaced or recirculated. If an air purifier’s ACH is two, for example, that means that it recirculates all the air in a room twice per hour.

How To Calculate

Thankfully, calculating ACH is pretty easy. Take the CFM of the air purifier, multiply it by 60, then divide that number by the room’s volume. The number you get is your ACH.

How Long To Run An Air Purifier Then?

Person's hand pushing a button on an air purifier.

The good news is that even with all those factors, there’s an easy answer when it comes to how long to run an air purifier. The answer is to run an air purifier all day. That’s right, all day! It is possible to clean a room’s air and turn the air purifier off, but pollutants will make their way back into that room’s air. Leaving an air purifier on all day removes as many pollutants as possible at all times.

Is There A Best Time Of Day To Run An Air Purifier?

If you don’t want to leave your air purifier on all day, the best time to run one is just before or when you’re in the room it’s occupying. Run it at as high a speed as you can for 30 minutes to an hour, then reduce it to normal speeds for the rest of the time you’re in there.

Are There Any Safety Issues With Leaving An Air Purifier On All Day?

Leaving an air purifier on all day causes no safety issues. You will want to change the filters regularly, clean them when needed, and pay attention to any odd issues, but it’s okay to leave it on all day. This will run up your electric bill, but there’s a way to figure out this cost.

How Much Will The Electric Bill Go Up?

If you’re looking for a more detailed way to figure out the cost of running an electrical device, the US EPA has a way to do that here and we have a way to do that here. Otherwise, there’s a pretty easy formula to use that can help you determine electric costs.

The first thing to do is to figure out how many hours you use the device per day. Then figure out how many watts the device uses. This can be found in the product’s information. After multiplying those two numbers together you divide them by 1,000 to get the kilowatt-hours per day.

Take that number and multiply it by how many days you use the device per year. This gives you the energy used by that device each year. Now, to figure out the cost, you take that number and multiply it by cents per kilowatt-hour, which varies from country to country and state to state.

Key Takeaways: How Long To Run Air Purifier For

Many factors affect how long to run an air purifier. The good news is that unless you need to turn the air purifier off at certain times, the best way to use an air purifier is to leave it on all day. This will increase your electric bill, but there’s a way to figure this out ahead of time, and it’s safe to do so.

So, how long do you plan to run your air purifier? What’s your reason for doing so? Let us know in the comments below!

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Hello, this is Randy Jones. I am the owner of this website “Home Air Wiki” which will inform you about all the latest home gadget tools like Air Purifiers, it’s related accessories, use, and maintenance information.

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