How Often Do You Need to Replace Air Purifier Filters?

How Often Do You Need to Replace Air Purifier Filters?

Air purifiers have become our silent companions, diligently working to keep our indoor air clean and breathable. However, the efficiency of these devices largely depends on the timely replacement of their filters. The question that naturally arises is: how often do you need to replace these filters to ensure optimal air quality? Let's delve into the answer, with a focus on our range of air purifiers.

Key Points Summary

  • The lifespan of air purifier filters largely depends on the air quality and the usage.
  • HEPA filters in our range typically last longer in cleaner environments like New Zealand, as compared to more polluted areas.
  • Carbon filters' lifespan can be tricky to determine due to varying levels of VOCs they tackle, but a ballpark is every 3-6 months for our Sqair or SA600 and longer for models with more carbon like our Blast and Blast Mini.
  • The absence of standardised testing across manufacturers makes comparing filter lifespans a tad challenging.

The Lifespan Labyrinth: HEPA and Carbon Filters

Air purifiers primarily employ two kinds of filters: HEPA filters and Activated Carbon filters. While HEPA filters trap minuscule particles, Carbon filters are your go-to for odor and gas absorption. Let’s explore their lifespans in a bit more detail.

HEPA Filters: The Color Cue and Real-World Ratios

dirty HEPA filter compared to new HEPA filter

HEPA filters work tirelessly to catch particles as small as 0.3 microns. Over time, these particles accumulate, and the filter becomes less efficient. A simple way to gauge a HEPA filter's lifespan is by checking its color. A filter that’s turned from white to gray or black is screaming for a replacement.

The lifespan of HEPA filters can significantly vary based on the air quality they are subjected to. Through real-world testing, we have estimated the following lifespans for our models:

 Model Lifespan (hours) Lifespan (months)
QT3 (Travel) 1200 10
Sqair 2550 10
SA600 4750 19
Blast Mini Mk II 7800 32
Blast Mk II 10200 42


These figures are based on the HEPA filter lifespan calculator from Smart Air and use average pollution levels in New Zealand. This may increase or decrease depending on the pollution levels where you live.

So, remember, the cleaner the environment, the longer your HEPA filter will last.

Carbon Filters: Playing the Smell Test

Determining the lifespan of carbon filters is a bit more complex due to the diverse levels of VOCs they encounter. The more activated carbon a filter has, the longer it will last. Our models use actual pellets of carbon, extending the lifespan significantly compared to some other models out there.

Carbon filters, when exposed to high levels of VOCs—as is common in newly renovated or constructed homes—can become saturated and lose their effectiveness much quicker than under regular indoor conditions.

To ascertain the effectiveness of your carbon filter, we recommend the “smell test”. It's a straightforward sniff test conducted on the carbon filter; if a sour or chemical odour is detected, it's time for a new filter. For more detail on performing this test, check out this link.

Sifting Through Standards: A Word of Caution

A noteworthy point is the lack of standardized testing for filter lifespans across manufacturers. A claimed lifespan of 12 months by one manufacturer might be based on just 4 hours of daily usage in low pollution conditions. It’s a murky area that makes comparison a challenge. This is why we provide estimates in both months and in hours of usage.

As a rule of thumb, filters with larger surface areas tend to last longer.

The Perks of Separate Filters

Our air purifiers are designed with separate HEPA and Carbon filters, allowing for targeted replacements. This not only is cost-effective but also ensures each filter operates at its peak efficiency for longer.

On the flip side, many air purifiers on the market come with 2-in-1 or 3-in-1 filter systems. While they might seem convenient, once one of the filters reaches the end of its lifespan, you are required to replace the entire set. This not only can be more costly in the long run, but also wasteful, especially if the other filters within the set haven’t exhausted their effectiveness yet.

By opting for our air purifiers with separate filter systems, you get to replace only what's necessary, extending the overall life and efficiency of your purifier while keeping replacement costs down.

Wrapping Up

Ensuring the timely replacement of your air purifier's filters is quintessential for maintaining a sanctuary of clean air in your home. With the right air purifier and a little vigilance on filter replacements, every breath you take can be a fresh one. Explore our range to find the perfect companion for your clean air journey.

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