The other day, a visiting friend asked me why I had left some windows open yet the air purifier was running. Wasn’t it bringing in contaminated air from outside? Would the purifier work perfectly as it should with open windows? Sometimes we may keep windows closed and sometimes open for fresh air circulation. The major question arising is how this may affect the air purifier’s performance.

Air purifiers circulate and filter air contaminants such as allergens, pet dander, smoke, microbes, pollen, mold and mildew, dust, and many other pollutants from the air. The air inside the house will then be clean and fresh as it circulates throughout the house. However, most people love the idea of letting in fresh air from time to time by opening up the windows.

So, one could wonder whether the air purifier will still work if the windows are open. On the surface, the answer is yes, but not as effective as promised because air purifiers perform more effectively in closed spaces. There are a few things to consider when deciding whether you should or should not keep your windows open.

Read on to get more insight into whether you can use your purifier with open windows.

So, Can Air Conditioners Work With Open Windows?

As already said, the air purifier will work with the windows open, but not as well as it should. Here is a good example of the working of a refrigerator to help you understand more about air purifiers. A fridge is meant to cool the air inside it. If you leave it open, there is no doubt it will still work by cooling the air near it as much as possible. The same case applies for the air purifier whose main task is to filter out contaminants from the air in the room. Even if you leave the window or door open, it will draw in air as much as possible and filter it.

However, the only limitation here is that the performance of the purifier in a room with open windows is less than one with closed windows. While still at it, the purifier the air in the room will not be as clean because contaminated air will still be getting into the room while at the same time some of the purified air will be escaping out through the openings. Ideally, this means that keeping the window open prevents the air inside from being as clean as it should. At every instant, the air purifier has to start afresh with the purification as contaminated air enters the room.

Should the Windows Always Be Closed When the Air Purifier Is Running?

This is not the case absolutely. You will need to open the windows from time to time to allow the air to circulate. However, do not keep the windows consistently open when the air purifier is running because it will hinder its performance and reduce the quality of the air in the room.

Opening of the door or windows once in while is fine. However, remember that in so doing, clean air particles will be escaping while contaminated air will be entering the house. Thus, ask yourself the following questions before opening the windows.

  • Is the air near the window that you are opening clean?

Find out how clean the air you are about to let in is. Is someone burning dirt nearby, is there dust being blown by the wind. If the surrounding air is filled with smoke, dust or any dirt particles, you may have to reconsider your decision of opening the windows.

  • Will you remember or you will forget to close the window afterward? How long will you be gone?

Time is a determining factor of air purity with open or closed windows and the efficiency of the air purifier (Click to see my air purifier reviews). The longer time you leave the window open, the less the work your air purifier can accomplish. It takes some hours for the air to be purified in a room. It would take much longer with the interruption of the air circulation with an open window. Thus, if you open your windows, do not forget to close them. Similarly, if you will be gone for long, it would be better not to open the windows at all.

Again, an open window does not mean that the air purifier will not work. It will, but not efficiently due to airflow disturbance. Contaminants will always be reintroduced in the room. Open windows mean that at any instance there will be some air in the room containing outside elements. This beats the logic behind having the air purifier in the first place.

However, this may not be much of a problem depending on your surrounds and the kind of pollutants present.

What Factors Should You Consider Before Opening Your Window

Before you decide that the windows should always be closed or open occasionally as you use your air purifier, consider the following conditions.

  • Surrounding Outdoor Environment

If you live in a polluted environment with smoke, car exhaust, or any other pollution issues, it is not recommendable to keep the windows open. Similarly, during spring, there is a high pollen count, and definitely not a good time to keep the windows open. Keeping the windows open under these circumstances will overwork the purifier, clog the filters much faster, and even reduce the lifespan of the purifier. More significantly, you will be prolonging the amount of time it takes for the air to be purified. Thus, only open the windows if you reside in a relatively clean environment.

  • Indoor Environment

If you own an air purifier, we can safely assume that the air inside your house is clean. However, certain things may prompt you to open up the window to let in the fresh air. Maybe your cooking just burned, or may there are some rotten fruits in the house, or some unpleasant smell coming from cleansers and chemicals or fresh paint.

The purifier may not get rid of such smells as fast as you would like, and in this case, it is advisable to open the windows. You will be reducing the air purifier’s workload and this is totally fine. However, note that the purifier will continue working whether the windows re-closed or not.

  • The Impact on Your Air Purifier

A purifier works at its best in confined spaces and closed windows because there are just slight disruptions. It takes in the air, cleans it, and sends it back as clean air. This is not the case when the windows are open. The purifier will keep work because more contaminants are entering the room. In the end, the machine is strained and this reduces its lifespan. To make the most out of your purifier, reduce the time that you keep the windows open. Increase its efficiency by closing the windows.

  • Energy

When you open the windows, you are giving room for the already filtered air to escape and for the outdoor contaminated air to get in. the air purifier will have to run for long to clean though it cannot achieve 100% purity as long as the windows are open. All this time, you are using up energy. As long as the windows remain open, you will notice that the air is unclean and thus the need to run the purifier longer. That adds up to more energy use and money wasted.

  • Health Conditions

If you are suffering from any respiratory problem, then you need the air inside your room free from allergens all the time. You may not have the time to gamble with opening the windows. Your best bet is closing the windows so that the purifier can take a relatively shorter time purifying the air.

How Many Open Windows Are Enough When The Air Purifier Is Working?

Your air purifier is at peak performance with the windows closed. It will still work if the windows are open. One window is ok. However, two or more open windows will make the purifier have no effect. With one open window, the purifier can work with marginal efficiency because the air disturbance is minimal.

Two or more windows facilitate more airflow but cause more disturbance around the purifier, interrupting the purification. This largely lowers the indoor air quality even if the purifier is still running. The best way to do it is by opening only one window in each room if you really have to.

When Should You Open or Not Open Your Windows?

Open or closed windows will not stop the running of your purifier. Open them if your outdoor environment is clean, if you do not have immediate allergy issues, or if you want to get rid of immediate extreme air problems like burns or garbage smell. However, remember to close them soon to increase your air purifier’s efficiency.

On the other hand, do not open the windows if your surrounding is heavily polluted, or if the air quality inside needs more time to treat. Most importantly, if you will be gone for long hours, it is better that you leave the windows closed.

Bottom Line-Windows Closed or Open?

The answer to this question is subjective. Consider opening your windows if your air filter is not running, or if you intend to keep them ‘open floor just a short while. If the air purifier is running, do not leave the windows open for long.

Overall, windows opened or closed, it really does not matter. The air purifier will just continue cleaning the air in the room, regardless. However, for maximum effectiveness, close both the doors and windows. If you choose to leave them open, the air purifier will clean the pollutants that come in.

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