What You Need to Know About Air Purifier Filter Replacement

What You Need to Know About Air Purifier Filter Replacement

The air purifier is one of the most important appliances in your home, especially if you suffer from allergies or asthma. But even the best air purifiers need to have their filters replaced every once in a while.

If you are not sure when it is time for a filter replacement, read on for some tips.

Why Is It Important to Regularly Replace Your Air Filter? 

Air filters are an essential component of air purifiers. They do the main task of trapping dust, pollen, mould spores and other impurities so that we can enjoy clean indoor air. However, air filters must be replaced on a regular basis to continue to be effective.

Here are the benefits:

Ensures Clean Air

Dirty air filters are less efficient in capturing particles. Dust build up may even cause your air purifier to release some of them back into the air, which is unhealthy. Replace air filters to ensure clean air constantly.

Prevents Machine Break Down

The air purifier device with clogged air filter will be compromised and or damaged if uncleaned. Regular filter replacement extends the life of the unit and will save you money on repairs or replacements down the road. 

Saves Money

Clean air filter will help the air purifier spew clean air, which helps reduce energy consumption and prevents your unit from working beyond its normal operating capacity.

How Long Do Air Filters Last? 

In general, air filter replacements should be done at least once every three months to ensure that the air in your home is clean and healthy. For specific kinds of filters, the recommended replacement time are:

  • HEPA filter: 12 months or 2–3 years
  • Activated carbon filter: 6–12 months
  • Mesh Pre-Filter: 2–4 weeks

However, this still depends on how much you use your air filter and the condition of the room.

When Should You Replace Your Air Filter? 

Most air filters will need to be replaced once they have become clogged with dust and other particulates, usually after around 3–6 months of use. However, there are some instances when air filters may need to be replaced more frequently or earlier than expected, such as if the air filter becomes damaged or begins to show signs of wear and tear.

Here are some signs that you already need a replacement:


If you notice that your air filter has started to dull in colour or lose its original shape, for example, then it may be time for a replacement. HEPA filters are an exception because they may appear darker despite only being used for a whilst.


You should also check whenever airflow decreases significantly in comparison with how it works when you bought it. If there is a build-up of dust in your filter, it will get clogged, which makes it harder for air to move.

Visible dust

If you are seeing dust on your air purifier’s vent, it means that your filter is already dirty. You can also test it by leaving a blank sheet of paper over your unit and letting it run for 30 minutes to an hour.


Some microorganisms like mould can cause your air purifier to produce a musty smell when they reproduce. If your unit is emitting any odour, there are high chances that you need to replace it. For carbon filters, if they can no longer absorb odours the way they used to, they should be replaced.

Those with medical conditions are getting affected

A dirty air filter will not be able to work the way it used to, so it can’t completely get rid of allergens. Stray pollutants will serve as triggers for someone with asthma or allergies.

How to Replace Your Air Filter 

Companies that make air purifiers usually offer subscriptions for their air filters. Usually, there are doors that you can open on the back, bottom or sides of your unit that let you access the location of the filters. Watch out if the filter bends or if there are visible gaps because they are signs that they do not have the exact fit with your air purifier. Using filters that are too big or too small for your unit will decrease its efficiency because the air will not be able to properly move.

To be safe, remember to keep the air purifier unplugged when replacing the filters and make sure that everything is locked and put back in place before using it again.

RENSAIR: The World’s Best Air Purifier 

If you are looking for an air purifier that you can use inside your home or commercial space, RENSAIR HEPA filter air purifier will ensure that you are getting the best indoor air quality. 

RENSAIR’s hospital-grade air purifier in Australia uses advanced purification technology, including a pre-filter, fan, HEPA H13 filter and a UVC light to trap pollutants and kill microorganisms. It is portable, easy to operate and no installation required. Plus, it has been tested by several independent laboratories including Eurofins, Norconsult, Oslo University Hospital and the Danish Technological Institute.

Contact us now for your enquiries.