
Air conditioners, a must-have equipment in these scorching summer days, have long been associated with cooling indoor spaces.
However, their reputation as air purifiers remains shrouded in uncertainty. Do air conditioners purify the air?
Let’s find in this article.
Does AC take air from outside?
No, air conditioners alone are not designed to bring in fresh air from outside. They work as sealed systems that use cool refrigerant to lower the temperature of the air in a room.

In a typical bedroom air conditioner, the air inside the room is pulled in, cooled, and then blown back out.
This means that the same air keeps circulating inside the room, and over time it can become stale unless you open a door or window to let in fresh air.
So, air conditioners don’t bring in fresh air on their own; they simply cool and recirculate the air that’s already inside the room.
Does air conditioner purify the air?
Your air conditioner works hard against the heat to keep your room cool and comfortable. However, when it comes to keeping the air clean from pollutants and debris, it simply doesn’t purify the air. At least not without a filter.
Just like a mask filters out Dust and particles from the air you breathe, an air conditioner filter plays a similar role. It traps and removes unwanted substances, ensuring that the air circulating in your room stays fresh and free from potential contaminants.
So, while your air conditioner fights the heat, it’s actually the filter that helps keep the air clean and healthy.
So, can air conditioner with good filter purify air?
The answer is, only to some extent.
According to Centers for Disease Control and Prevention (CDC), it has identified six pollutants as “criteria” air pollutants that affect human health.
- Carbon Monoxide
- Lead
- Nitrogen Oxides
- Ground-level Ozone
- Particulate Matter
- Sulfur Oxides

While modern air conditioners with filters can clean Dust, debris, and large particles like PM 2.5 (Particulate Matter), they cannot clean gaseous components of pollutants.
Air conditioners and improvement in air quality
No, air conditioners can not purify air completely. Still, there is no doubt that they can undoubtedly improve indoor air quality.
On the one hand, air conditioners can filter out Dust, debris, and particulate matter type large pollutant particles from the air. On the other hand, they can also regulate humidity in your room.
Poor humidity, whether it’s too high or too low, it can lead to the presence of mold, mildew, fungus, bacteria, and some viruses too.
However, remember if there is contaminated air, since your room is sealed, the air conditioner will eventually spread it all over your room. And you can also feel suffocation if you remain too long in a room with an air conditioner because of a lack of ventilation.
Do I need air purifier if I have AC?
Usually, you don’t need any air purifier with your ac; your air conditioner with good filter can clean large-size pollutants from the air and also regulate humidity in the room.
However, if you live in an area with poor air quality, filters alone can not control those pollutants. So in such cases, it’s good to have an air purifier installed in the room.
Conclusion
To summarize, air conditioners do not purify the air; however, modern air conditioners with good filters can clean air to some extent. But in areas with very low air quality, it is advised to only partially rely on ac.
FAQ
Does AC bring in the fresh air?
No, an air conditioner does not bring fresh air from outside to the inside of your home, it just circulates that already inside your room.
Does AC remove carbon dioxide?
No, AC can not remove carbon dioxide or any other gaseous components of pollutants.
Does AC air give oxygen?
No, AC does not produce oxygen. In fact, if your room is perfectly sealed and you remain there for a long time, then you may feel suffocation due to low oxygen levels.