An air purifier is a machine which is designed to circulate the air and rid the air of all irritants and pollutants such as microbes, allergens, pet dander and so on. However, fresh air is something that you should get to enjoy as time goes own. But how does leaving your window open affect your air purifier?

Do air purifiers work with windows open?

The thing about air purifier and open windows is a simple matter of efficiency. The air purifier will definitely still work when the windows are open but how efficient would it be. Let’s take a little example. The primary task of any refrigerator would be for cooling. It is designed to cool the air inside of it. Also, an air purifier is designed to remove the contaminant from the air that we breathe into our bodies.

If you leave a refrigerator open, would it stop working? No, the refrigerator would keep working as long as it is connected to a power source. This also applies to the air purifier in your room.

If you end up leaving your window and door open, the air purifier would still work and do its best to clean the air in the room around it. The only problem would be the machine’s efficiency.

Everyone should understand that air purifiers clean the air by making sure it cycles it. It draws the air from the room into it and then pushes back clean air into the room.

When you open your windows, you interrupt the cleaning process and the air will be exposed to contamination by different particles from outside the room. Before going ahead to open the windows, keep in mind that you will be making the air purifier work more or you would simply make it clean the whole room once again.

What you should really be careful about is what materials get into the room from outside and how much air gets into the room.

Does this mean that you would never get the chance to get some fresh air while using the air purifier?

No, this is not true. You can get to enjoy some fresh air alongside the clean air provided by the purifier but you would need to take a very close look at some factors. You would need to answer the following questions :

a) How clean is the air outside near the window you’ll have open?

Now, this question is very important to the well-being of the person in the room and can be a deciding factor to whether you should open the windows or not. Is the air around your home dirty, polluted, or smoggy?

Can you find anyone burning any pile of leaves close by? If you leave in an environment with a certain amount of pollution you should rethink about opening the window. Any air that is filled with smoke, trash, and particles should never get into the house. This type of air can be very dangerous for human health.

However, if you stay in a place with an environment which is free from pollution, leaving the windows open may not be a problem. But you will have to closely monitor the situation to prevent entry of any unwanted air particles.

b) Will you remember to close the window later, or do you plan to leave it open for hours?

This is also another important factor which you have to consider before opening the window. Time is a factor that determines if it is advisable to leave the window open or not. Exposure to unclean air for a long period of time will leave the whole room filled with unclean air regardless of the efficiency of the air purifier.

The longer you leave the window open, the less efficient the air purifier will be. It takes a long time to clean the air in a room. Keep in mind the time which the air purifier will spend cleaning up the air that has become contaminated.

Take note that if you leave the window open, the air purifier would still keep working to circulate the air. However, due to the disturbance in its operations, it may not be able to clean the air in the whole room. It may end up cleaning only the air close to it.

By leaving your window open, you are simply telling the air purifier to clean the air in the room and the air coming into the room from outdoors. So, as longs the windows are open, you will never have fully purified air in the room.

The air purifier can surely work when the windows of a home are open but it will experience a very good drop in the level of efficiency. It will work better in a sealed. A major problem with opening the windows is that allergens keep gaining entrance into the room despite the operation of the purifier. It will take a lot more time for the purifier to successfully filter all the contaminant that has newly entered into the room.

5 factors should be considered before opening a window

  1. The outdoor environment

Certain areas are more polluted than others. It would be very inappropriate if you live in a polluted area and you love to open your windows. You simply would never get clean air in the house.

Also, avoid leaving the windows open during the spring because of the high presence of pollen. Pollen travels very easily in air and can overwork the filter present in the air purifier.

Leaving the windows open in an area with smoke, exhaust and pollen simply mean more work for the purifier and the air quality in the room would be unable to reach high levels.

If you suffer from allergies, exposing yourself to allergens for just a short duration can be dangerous. Pollen and other pollutants easily lead to an allergic reaction. If you want to avoid any health conditions, open your window only if you live in a clean environment.

  1. The home’s indoor environment

Considering the presence of an air purifier, anyone can simply say that the indoor air in your home is probably good. That means something has caused you to open the window.

There could be a lot of reasons for that. Perhaps you just suffered a kitchen disaster and you need to get the smoke out of the house quickly. Maybe there is a pile of refuse in your house which you have failed to dispose of and you need fresh air quickly.

Also, repainting your walls can lead to homeowners dealing with a lot of fumes. There are a lot of reasons to open the window and some people just like having fresh air in the home.

Keep the opening of the window at a minimal level if you hope to get optimal results from your air purifier.

  1. The effect on your air purifier

It is easier for an air purifier to work in confined or sealed spaces because of little or no disruptions. The air purifier is free to circulate the air in the room at will. It continuously filters the air until the whole room is free of pollutants. Restricting the air that is cleaned by your air purifier is the only way to get optimal results from it.

  1. Energy costs

Considering the fact that your windows are left open, then the purifier would work more and consume more power. You may even be tempted to increase the speed of the fan to meet up with the demands of the air coming in from outside.

The machine would even have to work for longer to clean the air. This means you would steadily get an increase in your electricity bill. The air purifier is using more power and it would reflect on your bill.

  1. Time

This is basically concerned about the time it takes the purifier to clean the air in the room once the windows are closed again. Do your best to leave the windows open for only a few minutes. Leaving the window open for a few minutes will mean a lesser amount of time for the whole air in the room to get cleaned. However, if you leave the window open for hours or even days, you would spend a lot of time breathing bad air.

Want to know more tips about using an air purifier, read our article Best Tips for using an Air Purifier.


On a final note, your air purifier would still work with the windows open but at a lesser efficiency. Do your best to ensure you open the windows only when needed and for short periods. By doing this, you will keep air in your home at a very high quality.