Why We Developed the World’s First AC Air Purifier

5 min readMay 7, 2023

First questions first, why should we breathe clean air?

Imagine you are a fish swimming in a clean river. Now imagine someone put you in a muddy pond. Did you feel it?
When you breathe in polluted air, you are a fish in muddy pond. It is just that we are unable to see and sense air pollution, we tend to neglect it.

Thanks to news, we are aware of the issue of air pollution and best known solution till date is an air purifier. Do you have an air purifier?

If yes, I am quite confident like most people the air purifier must be somewhere in your home eating dust without being used. So basically you spend INR 10 thousand to 20 thousand and run your air purifier for 1–2 months out of 12 months. We understood that turning ON an air purifiers is not a habit. Since, we cannot sense polluted air we have a long journey ahead to make it a habit.

There are two fundamental problems with accessible clean air:
1. Cost constraint

2. Clean air doesn’t help in forming habit

1. Cost

After talking to hundreds of potential customers, it was evident that we have to break the cost barrier for clean air. Of course, we can’t just discover something new out of thin air that can reduce the pricing drastically. Only way left was to use existing infrastructure. We found that magical device to be an AC. Almost every urban home has an AC now.
Note: we are excluding rural areas for now because biggest source of air pollution for rural homes are cooking stoves. The easiest thing they can do is to take their stove outside, use better stove or use different cooking fuel.

2. Clean air doesn’t help in forming habit

A usual assumption people make while purchasing an air purifier that we will take one and move it to use in different rooms. Have you ever moved your air purifier?
People purchase air purifiers for their children or parents. In many cases when they are effected by allergy, asthma or some other respiratory issues.

But why are we late to prevent such health issues in the first place?
Again the problem is with sensing, you can’t sense polluted air but you will sense hot temperature and turn on your AC. This second fundamental problem again took us to our magical device i.e. AC.

Even before realising these fundamental problems, we observed something: not everyone at AIRTH was using our antimicrobial air purifiers :(
The message was clear: if people working at AIRTH have limitations with adopting our technology how can a common man will adopt it. We changed our strategy to focus on breaking the cost barrier for clean air rather than just focusing on the efficiency of the product.

By this point, we set our minds that we need to develop something with ACs. As the saying goes “stand on the shoulder of the giants” so we did our market research to find what are the solution available.
We found sheet filters are already there in the market being used in ACs.
We have our coating that can make these sheet filters capable to destroy germs that will be our USP (unique selling point) and let’s start asap but…

So close yet so far!

After testing existing sheet filters on several ACs, we saw negligible reduction in PM2.5 in real life conditions. It was heat-breaking for us…
Another problem is almost after 2 weeks of usage the filters gets choked and the airflow decreases drastically. We coated the sheet filters and tested again and found similar results almost 0% efficiency.

Reinventing the wheel…

We have no other option but to reinvent the wheel and think from the first principle itself.
We opened up an AC, understood everything around it and found the following constraints:
1. Surface area of the sheet filters was too low
2. Space availability inside the AC is almost nil

After spending a lot of time with AC, we observed we can use the top surface where the inlet is.

However, different ACs have different dimensions. We studied more than 100 AC filter dimensions via Amazon. Based on the data, we finally decided a length and breadth that can go with almost any 1 and 1.5 ton AC!!!

Another challenge: AC have curves and our system was unable to fit. We studies several types of foam which can take shape of the AC, their grades, advantages, lifetime among other parameters. We finally decided 10 mm thick foam basis on curvilinear design of ACs.

A non-compromising desire: no reduction in air flow!!!
People don’t want airflow reduction and this can kill our product.
As the first step: we studied CFD analysis to understand the airflow pattern. However, using anemometer we found that most of the air flows through the center. It is not uniform as usually shown in ads and graphics.

We tried sooooo many different configuration…and one of them worked the best i.e. coated HEPA in middle and two pre-filters on the side.

We believe we can disrupt the market where already existing sheet filters are no match to our product and air purifiers cost 5x to 10x than our product. We are trying to create a new category altogether and we know it is going to be tough.

See efficiency testing video by clicking here

Does our AC Air Purifier has limitations?
Short answer: YES

There is 10%–15% airflow reduction.
You have to replace filters every 8 to 12 months.
Our AC Air Purifier is not as efficient as an air purifier (unless you switch to winter version of our product).