GermGuardian AC4100 Air Purifier: Trusted Review & Specs

GermGuardian redefines what we should expect in an under $50 air purifier. In fact, the GermGuardian series has been the benchmark for exceptional budget air purifiers, and the lesser GermGuardian AC4100 strives to do the same at an even lower cost. Today, we are happy to give you the GermGuardian AC4100 Review to see if this air purifier still has enough gas in its tank for today or not.

GermGuardian AC4100 ranks D+ in our air purifier ranking list

Updated: The GermGuardian AC4200 is released now, with new design and 100% ozone-free air filtration system.

In Breathe Quality, we have reviewed all air purifiers under these sections. Also, we guarantee that:

  • We do give honest reviews (both pros and cons) so anyone will guarantee to have the wisest choices.
  • We do not (and never) exaggerate one product just to let you click the links and buy that product blindly.


germguardian ac4100 review

  • Decent air filtration process

  • Quite noisy at highest setting
  • Lacks of Smart features
  • Only 1-year warranty

With GermGuardian AC4100, the Guardian Technologies hits the ball out of the park with an impressive air purifier that offers plenty of value for under $50. There will always be some compromises on budget devices, and GermGuardian AC4100 is no different. But price is very much the spotlight of this air purifier, and it’s quite competitive given the solid features you get. In our GermGuardian AC4100 Review, we’ll take a deeper look at how this air purifier performs today.

Other GermGuardian’s Air Purifier Reviews:

GermGuardian AC4100 Price

For around $50, you will get this GermGuardian AC4100 with pretty high quality than common HEPA air purifiers in the same budget. I just can only think of the Hamilton Beach to be the possible competitor with GermGuardian AC4100 at this price.

Actually, GermGuardian AC4100 comes with an attractive price tag of $54, but with our up-to-date deal, you can find a more affordable device. In this segment, the most powerful rivals of this GermGuardian AC4100 could be the Honeywell HPA060, which has a great True HEPA filter. The Honeywell HHT270W is also an interesting alternative for the price.

UPDATED: We are now having the Levoit LV-H126, an air purifier with similar design with our today GermGuardian AC4100. However, this air purifier has True HEPA filter, and will be better than the compact device of Guardian Technologies. There is also a new upgrade to this family, thanks to the release of GermGuardian AC4200. It has good performance for an impressive price tag, so you shouldn’t miss it.

If you are looking for an air purifier for your kid’s room, you should read our GermGuardian AC4150 Review.

Top GermGuardian AC4100 deals right now

GermGuardian AC4100 3-in-1, 11-inch Desktop Air Purifier with HEPA Filter, UVC Sanitizer, and Odor Reduction.

The unique GermGuardian air filtration process is wrapped into this GermGuardian AC4100. A perfect option under $50 for your bedroom.

Related post: Best air purifier 2022.

GermGuardian AC4100 Design and Size

The GermGuardian AC4100 is a very simple-looking, non-showy little air purifier. Its body is plastic, there are no particularly attention to the total body and it cares much more about the super small size so you can grab anywhere.

At 11 inches in height and only 4.85 lbs in weight, this air purifier is one of the most compact air purifiers in the world. Only the Blue Pure 411 with 3.4 lbs, or SilverOnyx 3-in-1 can be lighter than this air purifier.

Still, GermGuardian AC4100 runs the same air flow process as its bigger brothers from this brand. That being said, this air purifier has a full-size air output grill from the front and another grill for air intake from the back. This design concept can easily maximize the fan power of GermGuardian AC4100.

There is no control panel as usual in other GermGuardian’s air purifiers. Instead, you will have only one switch, and one button at the front of GermGuardian AC4100. This air purifier is the most suitable for putting on desk or side table, so a set of button or switch on the front is totally okay.

germguardian ac4100 review

Source: Amazon

Related post: Best air purifiers for bedroom.

GermGuardian AC4100 Filters

For an under $50 air purifier, we weren’t expecting much in the performance department. Thankfully, the GermGuardian AC4100 surprised us with a typical 3-in-1 air cleaning system like the modern devices of this brand. Below are the air filters being used in this GermGuardian AC4100.

  1. Activated Carbon Filter – The normal carbon filter attacks smoke, cooking and pets odors along with harmful VOC’s emitted by common household products. In fact, this filter is a layer to be attached into GermGuardian AC4100’s HEPA filter.
  2. HEPA filter – GermGuardian AC4100 only uses a HEPA Filter to capture 99% of dust and allergens, pet dander, mold spores and plant pollen.
  3. UV-C Light – The unique 2W bulb with UV-C light to fight germs, kills airborne bacteria, viruses and mold spores.

Instead of separating Activated Carbon and HEPA filter to 2 physical layers, GermGuardian AC4100 combines these two to reduce the air filter’s size and increase the space within this air purifier. Of course, with only a HEPA-type air filter, the power of GermGuardian AC4100 can not compare with more expensive air purifiers. We have tested and can remind you that you shouldn’t expect a bump in performance rating for this air purifier. However, the combination with a powerful UV-C light bulb is the spotlight of GermGuardian AC4100. With it, there is very little bacteria, viruses or mold spores could harm you.

germguardian ac4100 review

Source: Amazon

Also, you need to change the air filter every 6-8 months. As the smallest air purifier in this line of GermGuardian, the filter replacement cost of GermGuardian AC4100 is also the lowest, with only $24. It is still a bit higher than Levoit LV-H132 or Blue Pure 411, though.

germguardian ac4100 review

Related post: Best air purifiers for allergies.

GermGuardian AC4100 Room Coverage

GermGuardian AC4100 is designed for a small room of only 100 square feet. You can’t expect a compact air purifier to cover a larger area, right?

The ACH of GermGuardian AC4100 is only 2X. This is one of the main cutbacks of the GermGuardian AC4100, with lower air changes per hour rating.

The CADR of GermGuardian AC4100 is 66 Dust/ 50 Smoke/ 76 pollen (cfm). Being an air purifier for small room, this GermGuardian AC4100 has a better fan power than even a double its price Levoit LV-H132, with only 40 cfm in CADR rating.

Related post: Best large room air purifiers.

GermGuardian AC4100 Sound

Running same 3 fan speeds like other bigger brothers, GermGuardian AC4100 may be one of the quietest air purifiers from this brand. You will not hear any sound on the lowest setting.

Unfortunately, this air purifier has a high pitched moan while running on high setting. And more importantly, it is hard to ignore. That’s why, GermGuardian AC4100 is clearly not the best option for quiet places, such as the office or bedroom.

For a quieter air purifier, you can look for the GermGuardian AC4150, costing only more than $10.

Related post: Best air purifiers for baby.

GermGuardian AC4100 Power Consumption

To be one of the best air purifiers, one device must strictly pass our Breathe Quality test after a long time use. Also, one of the most asked questions in Breathe Quality is: “Do air purifiers use a lot of energy?”. We can all agree that power consumption is one important criteria to review if this air purifier is worth your money or not.

Using an only 2 watts UV-C bulb, GermGuardian AC4100 has a truly energy-saving power consumption of 40 watts. The power consumption is not as great as Levoit LV-H132 or Blue Pure 411, but is still acceptable for a compact air purifier.

For using a GermGuardian AC4100 8 hours per day, it would cost you up to $15 per year.

Related post: Best air purifiers for pets.

GermGuardian AC4100 Additional Features

GermGuardian AC4100 is not for show off. So it is sad to say that there is no additional features on this air purifier. If you want a smart air purifier, especially a Smart Sensor for this price, you should look for the AeraMax 100 or SilverOnyx 3-in-1.

It is also superseded by the latest GermGuardian CDAP4500BCA which is released in 2017, so you should not expect much from an under $100 air purifier.

Related posts:

1, Best air purifiers for smoke.

2, Best air purifiers for dust.

3, Best air purifiers for mold.

GermGuardian AC4100 Customer Service

There is not much to say about the brilliant support from Guardian Technologies’s customer service. The American brand is providing a very active support for anyone contacting them. They also put the Instruction Manuals online to help you solve the common questions by yourself. But if you can’t find a solution, just contact the customer service via phone at 866-603-5900 or via email at Just like any other brands, they will be available for you from Monday to Friday.

They have occasional Free Shipping policy, as well as a great discount on all products (most popular 10% to 20%). Whenever you find their air purifiers not as great as you previously thought, you can return them within 30 days of your original receipt of the order. And don’t worry about the warranty policy of Guardian Technologies, as they warrant their products to be free of defects in materials or workmanship. You can register for a warranty in up to 3 years for the small devices, and up to 5 years for others.

However, for the GermGuardian AC4150 and GermGuardian AC4100, you will only have an 1-year warranty.

Top GermGuardian AC4100 deals right now

GermGuardian AC4100 3-in-1, 11-inch Desktop Air Purifier with HEPA Filter, UVC Sanitizer, and Odor Reduction.

The unique GermGuardian air filtration process is wrapped into this GermGuardian AC4100. A perfect option under $50 for your bedroom.

Our verdict

It’s not powerful and the HEPA filter is poor, but GermGuardian AC4100 once offered good baseline air purifier experience with a very little money. You can use this air purifier if other low-range GermGuardian devices are still a bit too expensive for your wallet.

At the moment, however, we can’t recommend this air purifier.

  • Performance
  • Features
  • Annual Cost
  • Design
  • Price


Not a good air purifier at the moment.