Best Filterless Air Purifier

Best Filterless Air Purifier In 2020 (No Filter To Change Ever!)

Depending on what angle you look at a filterless air purifier. It can be an eco-friendly machine that will save you a lot of time and effort in maintenance. An air purifier with no filter can also be looked upon as a sub-standard unit that falls behind a HEPA air cleaner. There are some that even argue on the usefulness as there is no filter involved. Whatever takes you have, we're here to rebut on the negative aspects and lead you to a whole new perspective on what the best filterless air purifier can do.

How Filterless Air Purifier Works

As the name implied, filterless air cleaner will purify the air without relying on any mechanical filter. Depends on the technology, it can cover a wide range of indoor pollutants like a normal HEPA filter would. There are 5 types of air purifiers in the market, one of those is the forbidden fruit that you should never go for.

  • Ionizer/ Electrostatic precipitatorElectrostatically charge and release negative ions to merge with positive ions particles. The merge particles would fall due to the increased weight and settle down in the purifier. There are slight differences between ionizer and electrostatic precipitators. The former is usually part of a HEPA air purifier filtration. The later is a standalone unit that comes with a collector plate to collect the fall particles.
  • Thermodynamic sterilization – aka heat sterilization or Airfree air purifier. Similar concept as boiling water that kills 99.9% of microorganisms and germs through heat. The sterilization process end with only normal temperature air released back out.
  • Hybrid – The main filtration must be a permanent filter or technology that is every green. While the supporting filters like carbon filter can be washable or replaceable. This enables the air purifier to work even if the rest of the filtration is worn out. Honeywell AirGenius 5 is a good example.
  • Ultraviolet UV cleaner – A conversational inclusion in the list as light bulb still has a usage lifespan. Uses UV-C/ ultraviolet from a light bulb to remove bacteria and viruses. The allergens are obliterated inside thus no cleaning ever needed. Modern UVGI cleaner comes together with ionizer which we have touched on earlier.
  • Ozone generator – This is the forbidden one we talked about. Ozone generator works through the process of oxidation. It split oxygen molecules (O2) into single atoms, eliminating any contaminants in between. The single atoms with merge with other oxygen molecules to form ozone (O3). Ozone generator is effective against odor, uses no filter but is harmful to our body. Inhaling to ozone can lead to many side effects and respiratory problems.
  • Photocatalytic oxidation – AKA Photocatalyst or PCO air purifier. Through the process of photocatalytic, a broad-spectrum UV light will react to titanium dioxide resulting in oxidization. As a result, PCO accelerates the natural decomposition of pollutants into harmless compounds. Photocatalyst is 100% safe, will eliminate microscopic bacteria and viruses, but the efficiency will degrade over time.
How Do We Measure?
The "permanent" filtration First and foremost, it must be filterless so any mechanical filter that require replacing will not be in this list. Next, the main filtration can be reused over and over again without expiring. Ionizer, UV-light, Electrostatic precipitator, heat sterilization, and Photocatalytic oxidation will all be considered except ozone generator. Any air purifiers that use ozone to clean the air are straight off the list. Lastly, we will measure its effectiveness against household allergens, smoke, and odors. The quicker it kills of the irritants, the more weight we will place on the air purifier.
Room size/ Coverage + Noise Level This one is a no-brainer. The larger the purifying coverage, the bigger the room size an air purifier can cover. As most filter-less air purifiers are not CADR tested, airflow delivery plays a key role here. The only "must" criteria is the noise level has to be silent throughout the entire operation.
Selling price Since filter replacement cost is nil. The air purifier selling price is a critical factor in deciding is this the "right" one. No point buying an expensive air purifier that does not work or take years to recuperate. We will also judge the unit worthiness when compared with a classic HEPA air purifier.

Who is this for?

Anyone from that needs clean air free from germs, smoke, and allergens. Busy parents or bachelor that do not need to be tied down with another home appliances. An asthmatic or hyperallergic person that is constantly sick. Newborn, baby and children would greatly appreciate it.
Want to stick with conventional HEPA purifying machine? Please visit Best HEPA Air Purifier.
other filter
With
UV-C Light Technology
Coverage
Coverage
56 sq. ft. (5 m2)

You can't have a filterless air purifier without introducing a plug-in air sanitizer. GermGuardian GG1100 Elite is the updated version to the popular GG1000 and now it comes with 2 colors (black & white). Unlike a conventional air purifier that is bulky with multisets of filtration, GG1100 Elite relies solely on UV-C light. A century-old technology that can kill bacteria and viruses within minutes. When microorganisms are drawn into the chamber, the spectrum ultraviolet light will penetrate the protective wall and altering the germs' DNA. The process will continue until all irritants and odors-causing cells are destroyed. Unlike a HEPA filter that heavily relies on a fan, UV-C light filtration is noiseless and uses very little electricity.

While GermGuardian GG1100 Elite takes up very little space as it is pluggable, there are some trade-offs to consider. First, there are some running costs as the UV lightbulb requires replacing every 6-12 months. GG1100 also has a very small coverage that you have to place it close to the pollutant sources e.g. next to the litter box, toilet bowl, or ventilation. Being a filter-free air purifier, the filtration depth is very restricted so do not expect similar quality as a HEPA filter. If you understand GermGuardian GG1100's limitation, there's is absolutely no doubt this sanitizer will work well as it is intended.

What's cool:

  • Affordable, UV-C air sanitizer that can be plug into a wall socket.
  • Filterless setup so no messy filter cleaning or replacing.
  • Great at removing bacteria, viruses, and mild household odors.
  • Zero noise operation and does not take up any interior space.

What's not:

  • Really small purifying coverage that you will need multiple units just to cover an entire room.
  • Not suitable for clearing dust, dirt, and hair.
MRSP/ RSP**
± 59.99 p
     Annual filter ^    
± 15 - 30 p
Online price*
Latest Amazon price
other filter
With
UV-C Light Technology
Coverage
Coverage
56 sq. ft. (5 m2)

The older version to GG1100 with the exact same functionality. GermGuardian GG1000 Pluggable UV-C Sanitizer is many people's favorite go-to air cleaner. It is small, affordable, and very easy to use. Just plug-in close to the contaminant sources and let the filterless air purifier quietly clean the air. You don't even have to worry about the electricity bill as GermGuardian GG1000 uses less energy than a standard lightbulb. Bacteria, viruses, musty mold, smelly toilet, and diapers all can be removed by the ultraviolet light. Perfect for tight spaces like toilet, kitchen, laundry room, and walk-in wardrobe.

Being a pluggable unit, GermGuardian GG1000 is very flexible with the placement. You can literally use it anyway as you please as long as it has a power source. You do have to replace the UV-light when it reaches its 5,000 expected lifespans. We recommend changing the lightbulb every 6 months or so as the performance will degrade over time. Another thing to take note that GG1000 is not a direct substitute for an air purifier. To gain the same filtration performance as a mechanical air purifier, you will need multiple units in a room. So if you plan to have only one filterless air purifier in your home, Airfree models would be the better choice.

What's cool:

  • Cheap, compact, and wall pluggable room sanitizer.
  • Uses UV-C light that silently cleans the air in the background.
  • No cleaning is needed. Simply replace the UV-C light bulb every couple of months.
  • Eliminate close range germs and household odors.

What's not:

  • Very limited purifying coverage (less than 60 square feet).
  • Poor against dust, hair, and other large airborne particles.
MRSP/ RSP**
± 39.99 p
     Annual filter ^    
± 15 - 30 p
Online price*
Latest Amazon price
other filter
With
Patented Thermodynamic TSS Technology
Coverage
Coverage
650 sq. ft. (60 m2)

Airfree Lotus is an air purifier without any single filter in its filtration. That's right, this filter-free air purifier that will purify your air with the single use of Thermodynamic TSS Tech. A purification method that relies on heat to kill germs. By drawing air into its chamber, Airfree Lotus will boil up the air to 400°F, effectively killing any microorganism in the process. This includes irritants like pollen, mold, dust mites, odors, ozone, bacteria, and viruses. When the air purifier is completely purified, air will be cool down internally and release back out at normal room temperature. The machine does feel warm when operating for long hours but not to the extent of causing any burn damage.

There are other perks of Airfree Lotus besides being a filterless air purifier. After 24 hours of non-stop operation, Airfree Lotus can cover room space up to 650 square feet. It is also very economical as there is no filter change or cleaning ever needed. At 7.7 x 13 x 7.7 in dimension, Airfree Lotus is very small and operates silently since there is no huge fan involved. For comparison, a typical mechanical air purifier is 2 times as bulky as a filterless air purifier. Perhaps the most critical factor of all, it produces no ozone and supports up to 10 multi-color night light. Perfect for a family that has children sleeping in their own room.

What's cool:

  • Patented Thermodynamic TSS Purification Technology.
  • No filter replacement ever needed.
  • Support up to 650 sq. ft. room size.
  • 10 selectable color night light.
  • Completely silent operation.

What's not:

  • Does not capture dust or any large particles quick enough.
  • To ensure consistent performance, Airfree Lotus must be turned on all the time.
MRSP/ RSP**
± 399 p
     Annual filter ^    
± 0 p
Online price*
Latest Amazon price
other filter
With
Patented Thermodynamic TSS Technology
Coverage
Coverage
180 sq. ft. (17 m2)

The cheapest, no fancy design, filterless air purifier that costs less than 100 (after discount). Unlike the above models, there is nothing special about Airfree T800 other than its compressed size. It does not have a night light, has a small 180 square feet purifying coverage, and topple easily. Why are we featuring it then? Simple. The no filter, water heating Thermodynamic TSS Technology is still here. Unlike a mechanical filter that traps airborne irritants, Airfree T800 can eliminate allergens permanently through the heat like boiling water. Allergens including mold, pollen, dust mites, viruses will be eradicated in the machine leaving only cool, clean air out. It is proven to be safe, maintenance-free, and eco-friendly from its filter-free setup. You will save a lot of time and money maintaining Airfree T800.

Airfree T800 downside is also its upside. Imagine having a super slim air purifier that can purify your air without the use of any filter. Being a filterless air purifier, it can work silently in the background without emitting any harmful toxic like ozone. Ideal for night use where you can place it next to your bed without disrupting your sleep. While it might not be as effective as a conventional HEPA filter, it is very cost-efficient that uses very little electricity. Best of all, T800 will kill germs, bacteria, and viruses similarly as its big brother would. What else could you ask for more?

What's cool:

  • Small, light, and portable.
  • Very cheap, around 3-4 times less than the normal model.
  • No filter replacement needed.
  • The same Thermodynamic TSS with the exact water boiling efficiency.
  • Completely silent operation.

What's not:

  • 180 square feet coverage is poor for Airfree standard.
  • There is also the slow purification process to contend with.
MRSP/ RSP**
± 159 p
     Annual filter ^    
± 0 p
Online price*
Latest Amazon price
other filter
With
Negative Ion Generator
Coverage
Coverage
<54 sq. ft. (5 m2)

The only pluggable, ionizer air purifier without filter in the list. Clarifion GL-139 Negative Ion Generator is a 100% maintenance-free air purifier with no recurring cost. Just pay for the one-off fee and you can reuse GL-139 again and again without fail. By leaving the filterless air purifier running in the background, millions of negative ions will be released into the air. The charged ions will then pull airborne contaminants down from the increased weight, leaving the air free of pollutants. You will then have to perform vacuuming to clean out the dropped particles. The ionization cycle is quiet and uses very little electricity even you are running the air purifier all day every day.

So what's bad about Clarifion GL-139 Negative Ion Generator? Like all pluggable air purifier with the tiny form factor, GL-139 can only purify up to 54 square feet of space. That's less than most mini air purifier out there. Ionizer technically doesn't remove any airborne contaminants in the room. Fallen dust, mold, pollen, and germs will stick to the wall, sofa, table, floor until it is cleaned or stirs back up in the air. Negative Ion Generator is also not great with smoke and odors. If those are your concern, a UV sanitizer will probably suit you better.

What's cool:

  • Filterless ionizer that does not need any maintenance or filter change.
  • Plug in compact form that does not eat up any interior space.
  • Zero noise output.
  • Use less than 1 watt of electricity.

What's not:

  • Requires vacuuming to actually remove the fallen airborne particles.
  • Less than 54 square feet of coverage.
MRSP/ RSP**
± 39.99 p
     Annual filter ^    
± 0 p
Online price*
Latest Amazon price
other filter
With
Patented Thermodynamic TSS Technology
Coverage
Coverage
250 sq. ft. (23 m2)

Filterless is Airfree. Airfree is filterless. This is how we would describe Onix 3000. A compact air purifier without filter that kills germ silently in the background. It uses Thermodynamic TSS Technology that applies the concept of boiling water. When airborne particles are pulled inside TSS ceramic core, the mini-ducts will heat up the air over 400 degrees Fahrenheit. The temperature now has exceeded the boiling point where microscopic allergens like mold, bacteria, and viruses will not be able to withstand the heat. With 99.99% of the contaminants eliminated in the core, the purified air will be cool down and release out at room temperature. The entire purification process is safe, proven, and without releasing any harmful ozone. In fact, Airfree Onix 3000 can even reduce ozone by 26% as tested in Sweden's laboratories.

There's a lot of similarities between Airfree Onix 3000 with Lotus. The silent, no filter purification, one-button operation, and night light (Lotus comes with more colors though). Great for bedroom use as there is zero noise coming out from the air purifier. Airfree Onix 3000 is also very compact and lightweight at only 8.4 x 10.4 x 8.4 in. You can place it on top of a cabinet or table without being too obtrusive. Performance-wise, it's no HEPA air purifier but that's the beauty of it. It is a filter-free air purifier so no costly filter replacement ever. If you don't mind the killing it softly purification, there are other mirroring models like Iris 3000, P3000, P2000, or just stick with Onix 3000.

What's cool:

  • Support up to 650 sq. ft. coverage.
  • Thermodynamic TSS Technology that destroys (note: NOT capture) microorganisms.
  • No filter change or maintenance ever needed.
  • Adjustable brightness night light.
  • Zero noise operation.

What's not:

  • Not effective against dust and other large particles.
  • Slow purification that would take days to cover an entire room.
MRSP/ RSP**
± 299 p
     Annual filter ^    
± 0 p
Online price*
Latest Amazon price

🏆 Honorable mention

Air purifiers come and go so no point featuring an air purifier that doesn't cut it anymore. Here are some memorable options:
  • Bionaire/ Holmes has many zero filter air purifier that is cheap and compact. Keep in mind a lot of the models are no longer in production. Avoid those.
  • Envion do carry a few iconic model that we have not reviewed (yet). Something you can ponder on.

📃 Previous holder

  • Lightair Signature IonFlow 50
  • Airfree P2000
  • Airfree Iris 3000
  • Bionaire/ Holmes Egg air purifier
  • Air Oasis 1000G3
  • Envion Ionic Pro Turbo

2020 Best Filterless Air Purifier

Air PurifierOnline Price (Amazon)TechnologyFiltrationCoverageScore
GermGuardian GG1100W/ GG1100B Air Purifier

$$$

CHECK PRICE
UV-C Light1-stage56 sq. ft. (5 m2)5.4
GermGuardian GG1000 Pluggable Air Purifier

$$$

CHECK PRICE
UV-C Light1-stage56 sq. ft. (5 m2)5.4
Airfree Lotus Air Purifier

$$$$

CHECK PRICE
Thermodynamic TSS1-stage650 sq. ft. (60 m2)7.6
Airfree T800 Air Purifier

$$

CHECK PRICE
Thermodynamic TSS1-stage180 sq. ft. (17 m2)6.2
Clarifion GL-139 Air Purifier

$$$

CHECK PRICE
Negative Ion Generator1-stage<54 sq. ft. (5 m2)5.4
Airfree Onix 3000 Air Purifier

$$$$

CHECK PRICE
Thermodynamic TSS1-stage650 sq. ft. (60 m2)7.8

 

Additional Information

Are Filterless Air Purifiers Good?

There are lots of benefits to own a filter free air purifier. A filterless air purifier can clean indoor air 24 hours a day even when you're asleep. You can safely leave it running all day without having to worry any noise distraction. Because the air purifier has no filter and complicated components, expect a fairly small and lightweight body. A filterless air purifier also uses very little electricity and will save you a lot of money over time. Since there is no filter to clean or replace, zero maintenance is needed during the entire ownership. Compared that with a mechanical air cleaner that needs filter change every 6 to 12 months.

In short, here are the pros of owning a filterless air purifier.

  • No recurring filter replacement cost.
  • No maintenance or vacuuming needed.
  • Affordable price range even for the top tier model.
  • Lightweight (less than 4 lb).
  • Noiseless operation.
  • Energy efficient.
  • Simple operation with one touch function.

While here are the cons with a filterless air purifier.

  • Single filtration VS multiple filtrations found in a mechanical air purifier.
  • Less effective than a conventional HEPA air purifier in cleaning the air.
  • Not very effective in removing smoke and odors.
  • Has fewer features (no timer, auto mode, remote control) and options in the market.
  • Most models are not officially certified by AHAM.

Is It Safe To Leave A Filterless Air Purifier On All The Time?

A filterless air purifier is perfectly safe to run 24 hours a day without shutting down. It is designed to do so to prevent airborne contaminants like dust, bacteria, and viruses from building up when it is off. Just turn on the air purifier, go on with your day and let the machine do the air cleaning.

Are Filterless Air Purifiers Safe To Use Around Children And Pets?

A filterless air purifier is safe to use around babies, children, and pets providing it is not an ozone generator. Even models like Airfree that uses thermodynamic sterilization (heat) will not cause any burn damage. Most filterless air purifier is very compact too so there is less hazard risk of the air purifier accidentally topple and knock on the little one.

Will Heat Sterilization Increase The Room Temperature?

Heat sterilization will not heat up the room temperature despite performing the sterilization at around 250°F (121°C) to 270°F (132°C) degrees. This is because the heated air will be cool down within the air purifier before releasing clean air out. The air purifier might feel warm when touched, but in no ways the heat will be transferred out.

How Do I Choose A Filter Free Air Purifier Based On My Room Size?

Choose a model with the recommended coverage equal or exceed the square footage of your room size. For example, if you need the air purifier to work in a 300 square feet room, pick a model that can cover at least 300 square feet of space. Since filterless air purifiers are not under AHAM CADR ratings, you will need to rely on the official figures from the manufacturer.

To calculate your room size in square footage, just multiply the length and the width of the room. E.g. length 20 feet x width 20 feet = 400 square feet.

Do Filterless Air Purifier Release Ozone?

Filterless air purifiers will not release ozone unless you account for ozone generator. Ozone generator or Ozonator is a device that produces ozone that is harmful to our health especially our lungs. It breaks apart oxygen molecules in the air into single atoms, then merges with other oxygen molecules to form ozone. Because ozone is an unstable compound, it can react badly with other toxic chemicals found in a household like VOCs, cigarette smoke. None of the filter-free air purifiers listed here is ozone generator as we do not advocate owning one.

Is Ionization Or UV-C Light In Filter-free Air Purifier Safe?

Ionization, UV-C light is safe to use and will post no threats to human health risk. It is a proven technology that has been used for decades commercially and residentially. Ionizer produces natural negative ions to remove airborne irritants. UV air purifiers use ultraviolet rays to safely kill bacteria and viruses inside the chamber. Most people will confuse ionizer as an ozone generator which is a totally different set of technology. A true ionizer does not generate ozone to "purify" the air.

Why Most Filterless Air Purifier Does Not Conduct ACH Or CADR Ratings?

Most filterless air purifier technology is not designed to be rated with CADR or ACH. Both tests are only applicable to air purifiers with a mechanical filter and fan to draw air in. It does not measure how many microorganisms that have been removed or killed in the process. CADR or Clean Air Delivery Rate measures the volume of clean air in CFM (cubic feet per minute) at fixed room size. 3 tests will be conducted separately for different ratings: dust, pollen, and smoke. ACPH or ACH is the abbreviation for Air Changes per Hour. A metric that measures how many times the air purifier exchanged the air from a space. A filterless air purifier relies on heat, ultraviolet light, or ionizer to clean the air.

Does Filterless Air Purifier Remove Odor?

Filterless air purifier like ionizer or UV-light does remove odors from mold, pets, toilet, cooking, and chemicals like tobacco smoke, cleaning agents, VOCs, and CO. It is however, less effective than a mechanical carbon filter that can handle even the finest smoke particles. If your home is plagued with a musty, obnoxious smell all-year-round, there's no harm trying it out with an air purifier.

What To Look For In a Filterless Air Purifier

There are not many 100% filter free air purifiers in the market. Most models come in a hybrid form that has at least one reusable filter. If you already set your heart on one, here are some great features you should take into account when buying a filterless air purifier. The more knowledge you have on a product, the better decision you will make.

  • Filtration performance - The most important factor in choosing a filterless air purifier. With different technologies in place, not all air cleaners come with the same filtration quality. Pick the model that offers the highest filtration percentage in eliminating airborne particles like dust, mold, pollen, germs, bacteria, and viruses.
  • Coverage - The higher the coverage the better. Knowing the room size you need will make a big difference. Some models can only cater to a small space while some can cover up more than 1,000 square feet. For example, if you need to place an air purifier in a 300 sq. ft. room space, pick a model that can handle at least the minimum range.
  • Features and technologies - A good determining factor on which air purifier you should go for. For example, there are models that clean the air using solely UV-light while some with be focusing on negative ion generators. Filterless air purifiers like Airfree will be using Thermodynamic TSS Purification Technology instead. Depending on your lifestyle, features like a night light, timer, or mood light are also worth ponder upon.
  • Dimension - If you are staying in a very limited room space area, it makes sense to choose a compact and portable air purifier. An air purifier with no filter can be very small and lightweight compared with a HEPA air purifier. Some models even come in a pluggable form that you can plug it into the wall or bring it around for travel.
  • Noise output - The biggest perks of owning a filter-free air cleaner. Filterless air purifiers are noiseless and will run it silently in the background. Ideal for workspace, bedroom, nursery room, or anywhere you need your mind to stay focus on. Pick the model that has a noise level of less than 20 dB for minimal distraction.
  • Energy consumption - The powerful the air cleaner is, the more energy is needed. That said, the non-dependable of a conventional motor fan makes filterless air purifiers very energy-efficient. Any model you pick will have little impact on your electricity bills.
  • Warranty - The longer the period, the better assurance you will get from the manufacturer. Even though filterless air purifiers rarely break down, it will give you peace of mind during the course of ownership. Also, consider the service center location and what parts does the warranty cover. Brands will notoriously bad track records should pay close attention to this.