Why Is My Costco Air Purifier Quality Light Yellow?

Last Updated on March 29, 2024

Just like any of the advanced air purifiers out there, the devices from Costco come with an air quality indicator. This indicator helps the users know the overall air condition in the indoor environment.

Now, when you notice the indicator light while the unit is operating, you might wonder why is my Costco air purifier quality light yellow. Well, when it is yellow, it means that the air quality is average. On the other hand, if the air quality is good, the light would have been blue.

So, how do you make the air quality light turn blue? To learn the process, you should go through everything we will discuss in this article.

What Does the Air Quality Light State?

Before we talk about the process of making the light turn blue, let’s talk a little bit more about the air quality indicator. So, this indicator will show information with three different light colors. Blue states that the air quality is good, amber or yellow states that the quality is fair, and red means poor.

However, you will not get the exact information after turning the device on. In the first 30 seconds, the indicator will cycle through the three different colors. And the smart sensors of the Costco air purifier will take around 4 minutes to precisely gauge the air quality of the environment. After that, you can get an exact reading.

How to Make the Air Quality Light Turn Blue on Costco Air Purifier?

Yes, the air quality light states the condition of the air around you. But there are some things that can make the indicator show inaccurate reading. And if you consider these points, it will be possible to get an accurate reading out of the air quality light:


Before anything else, consider the placement of the air purifier. Remember, you should not set the air purifier in the corners of your room. That is where the air does not circulate that efficiently. And when there is no proper circulation, the device will struggle to purify the environment, which might make it show an inaccurate light.

Instead, the best placement for the air purifier would be in the middle of the room. The device can efficiently take the air and exhaust clean air into the environment. That will eventually make the indicator offer accurate light.

Clogged Pre-filter or Carbon Filter

Usually, there will be three different filters in the Costco air purifiers. Among them, two of them are connected to the filter indicator light, which are the carbon filter and the HEPA filter. The air purifier will not offer any alert at all when the pre-filter is clogged and needs cleaning.

For that reason, you should not forget to clean the pre-filter after every 14 days. A clogged pre-filter can make the air purifier struggle to draw air in and put out clean air into the environment. And as you might have guessed, that will eventually make the smart sensors offer an inaccurate reading.

You also need to keep the AOC carbon filter clean with the pre-filter. However, it does not require that much frequent cleaning, and the filter indicator light will tell you when to wash it. Nonetheless, it generally needs cleaning after every three months. And you would need to replace it after every 12 months.

The HEPA Filter Needs Replacement

The Costco air purifiers’ HEPA filter will last up to 12 months. After that, you will need to get it replaced. You can not wash this filtration unit as it is not washable. However, if you do not get it replaced at the right time, the air purifier will not be capable of effectively cleaning the air, which will make it offer red or yellow light.

Final Words

Still thinking why is my Costco air purifier quality light yellow? Well, the yellow light states that the room’s air quality is average. And if you want to make it turn blue, which means that the air quality is good, you need to check the air purifier’s placement and filters.

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Paul M Walker

I, Paul M Walker, am the founder and the author of this little site you are currently on. I work to provide readers with no-fuss and easy-to-follow solutions regarding common air purifier and humidifier problems.

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