How Often to Change Air Purifier Filter? Replacement Guide

How Often to Change Air Purifier Filter? Replacement Guide

We all know air is the most important component for the survival of life on Earth. But still, most ‌people don’t give a second thought to the quality of the air they breathe. As more gasses are pumped out daily from factories, cars, and planes, ‌air quality is being deadly affected.

It's impossible to control the outdoor air, but you can control the indoor air by installing an air purifier. If you have it installed, you know how it plays a vital role in improving air quality.

However, like any other electronic device, your air purifier also has a certain lifespan. Without proper care and maintenance, it will soon be out of function. That is why changing your air purifier filter is important.

In this blog post, we will discuss why, when, and how to change your air purifier filter.

How Often to Change Air Purifier Filter?

There is no one-fit-all answer to this. The frequency of changing your air purifier filters depends on the type of filter, its usage, and the quality of indoor and outdoor air.
Below are general guidelines to help you determine an appropriate schedule:

HEPA Filters

If your device has ‌‌High Efficiency Particulate Air (HEPA) filters, it is recommended to change them every 12 to 18 months. However, if you or any family member smokes or you have a pet, you should change it every 6 to 9 months.

Activated Carbon Filters

These filters should be replaced every 3 to 6 months, depending on where you stay. If you stay near factories or airports, you might need to replace them more frequently.


Usually, most pre-filters are washable. So washing it every 2 to 4 weeks will do the work. For replacement, generally, 3 to 6 months is recommended.

Usage-Based Replacement

If you use your air purifier continuously for a longer period of a day, you might need to replace it more often, every 2 to 3 months. Also, make sure to check the filter every 2 to 4 weeks, and replace it as needed.

Manufacturer's Recommendation

Generally, the recommended replacement period will be every 6 to 12 months. Even if you don't use your air purifier very often or don't see dust in the filter, you should still change it as per the manufacturer’s recommendation.

Factors That Affect the Service Life of Air Purifier Filters

The service life of a purifier is not universal. It differs from brand to brand, the type ‌of air filter used, and many other factors.

1. Type of Air Purifier and Filter

Depending on the purifier brand and the filter it uses, the life span can differ. For example, the MSA3 HEPA Pet Air Purifier has a longer life span compared to air purifier brands that use carbon filters.

2. Air Quality and Pollution

If you live in the middle of a busy city, or near ‌industrial areas where the environment is highly polluted. Your air purifier filter will have a shorter lifespan, leading to more frequent filter changes.

3. Frequency of Use

If you keep your air purifier on for most of the time during the day, expect to replace t more often to maintain efficiency. Though using it occasionally leads to a longer filter life, it will still need a check-up and maintenance once in a while.

4. Humidity and Temperature

Environmental conditions can also play a role in the life expectancy of your air purifier. For example, high humidity can carry larger amounts of dust and allergens and clog the filter fasters. High temperatures, on the other hand, can cause the device to heat up and reduce the effectiveness of certain filter types, impacting overall service life.

5. Presence of Pets

If you have pets at home, expect to replace the air filters more often. Pet hair, dander, and dirt from their bodies can accumulate in the air and get stuck in the filter. Grooming your pets and vacuuming your spaces can help extend the life of your air purifier, but grooming and vacuuming every day is not possible.

How to Determine Whether the Air Purifier Filter Needs to Be Replaced?

The best way to increase the efficiency of your air purifier filter is to know when to replace it. While the manufacturer’s guidelines provide a basic schedule, several signs can indicate it’s time for a replacement sooner than anticipated.

1. Decreased in Efficiency

If your air purifier is making unusual sounds, or you notice a reduction ‌in air quality or an increase in respiratory ‌discomfort, these could be clues that the filter is clogged.

2. Visible Dirt and Debris

Seeing dirt and debris stuck to a filter is normal, but if it appears heavily soiled beyond simple cleaning, it’s time to replace your filter.

3. Unpleasant Odors

You’ll see this type of problem in activated carbon filters. If you’re getting an unusual smell in the room, it means the filter is blocked and can’t trap odor-causing particles anymore.

4. Increased Allergy Symptoms

Air purifiers such as the MSA3 HEPA Pet Air Purifier are known to reduce allergen particles such as pollen, pet dander, and dust mites. But if you or your family member starts experiencing heightened allergy symptoms indoors, it might be due to a clogged air filter. It’s time to replace it!

5. Indicator

Most air purifiers come with a filter replacement reminder. For example, the MSA3 HEPA Pet Air Purifier, this device has a replacement reminder that you can manually set. So, regardless of how often you use the purifier, if the indicator starts glowing, it's time to get a new filter.

How Do I Change My Air Purifier Filter?

Changing the air purifier filter can differ from brand to brand, but the steps generally involve a similar process. Let’s take the MSA3 HEPA Pet Air Purifier as an example here.

Step 1 - Power off the unit and disconnect it from the electrical source.

Step 2 - The MSA3 has a front panel that you need to open by gently pulling the bottom towards you. (The removal panel could be either at the front or the back, which may require sliding, popping, or unscrewing it, depending on the design and brand.)

Remove the cover of MSA3

Step 3 - Remove the old filter system, which includes a pre-filter, HEPA filter, and active carbon filter.
Remove the old MSA3 air purifier filter and replace it with a new one

Step 4 - Before inserting the new filter, wipe away the dust and debris with a dry cloth. Make sure not to touch or damage any components. Replace it with the new filter elements in the same order.

Step 5 - Close the panel securely and reconnect the power.
These steps are all changes to your MSA3 HEPA Pet Air Purifier filter, but if you’re not confident in doing the job, it’s always wise to consult a technician.
Install the MSA3 air purifier

For more detailed instructions or to purchase replacement filters for the MSA3 model, you can visit the MSA3 Air Purifier Filter here.

What Happens If I Don't Change My Air Purifier Filter?

If you don’t change your air purifier filter, you’re not only neglecting the efficiency of the device but also your overall health. You bought the purifier because you want to breathe in healthy air and live a healthy life, right? So why neglect ‌changing the filter?

Here are the drawbacks of not changing your air purifier filter.

1. Decreased Efficiency

The lifespan of any electronic device depends on how much stress you put on its motor. The same goes for air purifiers. When you don’t change the filter, the collected dirt, pollen, and other airborne particles can obstruct the airflow, making the device work harder.

When your device works harder than it should, there is a high chance of wear and tear on its part and a likely mechanical failure.

2. Increased Energy Consumption

Compared to the overall air purifier, the filters are not that expensive. If you still think it’s an unnecessary cost, think about the increasing electricity bill. When your device works harder, it starts to consume more electricity than it should, leading to higher electricity bills.

A clean filter enables your air purifier to run more efficiently, reducing energy consumption and ultimately saving you money on your electricity bills.

3. Poor Indoor Air Quality

The number one reason why most people buy air purifiers is to increase ‌indoor air quality. Now, if the device stops producing quality air, what is its use?

When you don’t change your air purifier filter regularly, the device stops capturing and trapping harmful particles from the air, leading to aggravated allergies, asthma, and other respiratory conditions.

4. Increased Health Risks

If you leave the filter unchanged for long, sooner or later, mold and bacteria will make it a breeding ground. This can create unpleasant orders and potentially harmful air conditions.

Changing your air purifier filter gives you clean air to breathe in and reduces the risk of respiratory issues, allergies, and other health problems that can arise from breathing in contaminated air.

Can I Clean My Air Filter Instead of Replacing It?

Cleaning can increase ‌the lifespan, but you will need to do the cleaning every 3 to 4 weeks. Sometimes cleaning at this frequency becomes impossible, and this is when the debris and dust get a chance to enter your air purifier.

Another problem is that repeated cleaning can compromise the integrity of the filter material, leading to decreased performance over time. Besides this, carbon filters are not washable. You can wash HEPA and pre-filter, but carbon filters need to be replaced as they lose effectiveness.

Furthermore, no matter how much you clean the filter, it might not completely remove viruses, bacteria, or mold spores. Replacing your filter is not only recommended but becomes compulsory in most cases.

Healthy Air for Healthy Life

The air filter is the most important component of any air purifier. It works as a backbone for the device. If it stops doing its work, the whole purpose of the air purifier becomes useless. For that reason, maintaining and replacing your air filter is crucial.

To simplify maintenance, set a timer on the device if it has one and keep a spare filter on hand to avoid any downtime in air purification. Once the indicator light starts blinking, take‌ some time to clean and replace the filter if possible.

With careful attention to these details, your air purifier will continue to function effectively, providing you with clean, healthy air day in and day out.

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