GermGuardian AC5109W Air Purifier: Trusted Review & Specs

When you think of an oddly named air purifier, GermGuardian should be your top pick. When the GermGuardian AC5109W came out, even us, who have tested nearly 30 devices from Guardian Technologies, didn’t know whether it was a budget or mid-range device. The new air purifier is a mid-year iteration on the top flagship of the brand, and we will find out its pros and cons in the GermGuardian AC5109W Review.

Update: The most powerful air purifier you can buy from Guardian Technologies is the GermGuardian AC9600W.

GermGuardian AC5109W ranks B in our air purifier ranking list. We give the biggest and most thorough database of air purifier reviews in the world.

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

  • We provide honest reviews (both pros and cons) so that everyone can make the best decisions.
  • We do not (and never will) exaggerate one product just to let you click the links and buy that product blindly.


germguardian ac5109w review

  • Most powerful while not being the most expensive
  • Energy Star rating
  • Smart Sensor
  • 3-year warranty

  • Filter replacement cost is a bit high

Guardian Technologies is one of the best air purifier brands at the moment. Its products are backed up by an amazing 3-year warranty, even for the budget devices that are under $100. The GermGuardian AC5109W is a next-gen air purifier from the company, featuring a Smart Sensor and a new air filter. In this GermGuardian AC5109W Review, we will see if the new device can achieve such success that the GermGuardian AP5800W has.

Other GermGuardian’s Air Purifier Reviews:

GermGuardian AC5109W Price

The GermGuardian AC5109W price is all over the place, and that’s part of the problem. It officially costs $399, giving it the title of “GermGuardian flagship,” along with the GermGuardian AC9600W and GermGuardian AC9400W, according to Guardian Technology. However, on other marketplaces, it costs $319 or $349, according to Amazon and Walmart, in the U.S.

It’s still too expensive for an air purifier of this class. Let’s have a look at the Coway AP-1512HH, Blue Pure 311 Auto, and Winix AM90; they’re by far the best air purifiers of this era, and none of them come close to the price of the GermGuardian AC5109W.

Surprise. It’s “on sale” for $239. How do we even judge that against the competition? Who knows how long these “introductory promotions” will last?

Guardian Technologies has good air purifiers—actually good “budget” air purifiers. Any attempts in the mid-range should learn from the previous success, especially when the competition is really tough right now. The GermGuardian AP5800W is a good example, so why doesn’t the GermGuardian AC5109W be?

Top GermGuardian AC5109W deals right now

GermGuardian AC5109W 6-in-1 Hi-Performance Air Purifier with HEPA Filter, UV-C, and ionizer.

Strong performance with all air filter types possible. Auto Mode for dealing with allergens and viruses automatically. Energy Star rating.

Related post: Best air purifier 2023.

GermGuardian AC5109W Design and Size

The GermGuardian AC5109W follows the new design of modern GermGuardian air purifiers discretely, as it is a bit different from the GermGuardian AP5800W and GermGuardian AC9600. It is 23.5 inches in height and 13 inches in width, making the GermGuardian AC5109W’s size the average of its brothers.

With an initial price as high as the flagships of Guardian Technologies, you could expect a well-built air purifier. The air purifier is heavier at 13 lbs, but it is still the GermGuardian formula, so it’s difficult to move it anywhere in your home because it has no convenient handle.

It’s trending now to have a tower-like air purifier with a 360-degree air inlet, like the GermGuardian AC5109W. Levoit Core 600S also did it, and I must say this could be the best air purifier for another year. So for the design concept, the GermGuardian AC5109W is kind of okay.

The problem is, the GermGuardian AC5109W doesn’t feel like a mid-range air purifier, and it’s sad for a long-time air purifier brand like Guardian Technologies. The design of its air outlet doesn’t catch my eye, and the placement of its buttons is just terrible. The AQI screen is decent, but I still think keeping it as simple as the AP5800W is better.

germguardian ac5109w review


After testing so many GermGuardian air purifiers, even the modern ones, I have just one big issue: it doesn’t have any standout features or even ones that differentiate it from the pack. Such an unremarkable design should be changed.

Related post: Best air purifiers for bedroom.

GermGuardian AC5109W Filters

If the design doesn’t strike you, perhaps the performance would be the main selling point of the GermGuardian AC5109W. Another new all-in-one air filter is available for the new product, and this time it is one of the highest-quality air filters. Keep in mind that this is the first GermGuardian air purifier to introduce all air filter types in its 4-stage air cleaning system.

  1. Pre-filter – Using the Activated Carbon filter, this layer of air filter can remove most of the large particles of pollutants and reduce odors created from smoke, cooking, and pets.
  2. True HEPA filter – The GermGuardian AP5800W makes use of a True HEPA filter to capture 99.97% of microscopic allergens, dust, and mold spores down to 0.3 microns in size.
  3. Ionizer – It implements the flagship’s ionizer to enhance its ability to remove particles and keep the air fresh. Can be switched on/off.
  4. UV-C light filter – The signature filter of GermGuardian actually destroys the germs, bacteria, and viruses.

The GermGuardian AC5109W not only inherits the ionizer that was previously featured in the GermGuardian AC9400W, but it also retains the brand-aware UV-C light bulb. The power of a UV-C light filter isn’t about trapping dust that you can see; it reliably destroys bacteria and viruses by sterilizing the microorganisms.

One thing to remind you is that the air purifier can only kill bacteria and viruses with direct exposure to radiation. So if the viruses linger on the surface of your furniture, an air purifier won’t have any effect. The GermGuardian AC5109W could be one of the best air purifiers for mold and mildew, as mold and fungi spores do float in the air.

Well, it seems the new air filter of the GermGuardian AC5109W is very effective. It isn’t the best, yes, but it is far from the worst. The GermGuardian AC5109W can clean 99.9% of any particles down to 0.3 microns. Not to mention the UV-C light filter can’t be tested, as it can kill germs and prolong the life of air filters.

It is behind the Blue Pure 211, Levoit Core 600S, and Medify MA-40, but not by much. As you can see, the GermGuardian AC5109W is still better than other competitors in the same price range, like the Filtrete FAP-ST02.

germguardian ac5109w review

The new air filter O FLT5100 costs around $79, like the cheaper GermGuardian AP5800W. It is still recommended to change after 6 to 8 months.

Related post: Best air purifiers for allergies.

GermGuardian AC5109W Room Coverage

If you are looking for the room coverage of a GermGuardian air purifier, specifically the GermGuardian AC5109W, you will get the “true” suggestion from the Association of Home Appliance Manufacturers (AHAM). The GermGuardian AC5109W is suggested for use in a room of 394 square feet.

The ACH of GermGuardian AC5109W is 5X. By cleaning your space every 12 minutes, the GermGuardian AC5109W can fully clean 394 square feet in 1 hour.

The CADR of GermGuardian AC5109W is 258 Dust/ 254 Smoke/ 291 pollen (cfm). It is by far the most powerful GermGuardian air purifier.

Related post: Best large room air purifiers.

GermGuardian AC5109W Sound

The next-generation GermGuardian air purifiers do a very good job at keeping their powerful fans quiet, and the GermGuardian AC5109W can keep the noise level as low as 28 decibels (dB). For reference, it is quieter than a whisper.

The highest speed of the GermGuardian AC5109W is just 56 decibels. It’s okay for most situations, and the white noise in the Medium setting can help you sleep better.

Related post: Best air purifiers for baby.

GermGuardian AC5109W Power Consumption

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

As an Energy Star air purifier, the GermGuardian AC5109W is supposed to be energy-efficient. Its maximum rated power is 65 watts, so it isn’t as good as the older flagships like the GermGuardian AC9200WCA.

However, using an Energy Star air purifier is recommended, as the GermGuardian AC5109W only costs you $23 per year for running it 8 hours per day.

Related post: Best air purifiers for pets.

GermGuardian AC5109W Additional Features

Smart Sensor is already in the GermGuardian AP5800W, so it isn’t a surprise to see it again in the GermGuardian AC5109W. The air sensors are pretty good, with both dust and gas sensors to detect even the smallest airborne particles.

Why a smart sensor, you may ask? For first-time readers of Breathe Quality, it is necessary to have a smart sensor in your air purifier because it will react accordingly to changes in air quality. Then, thanks to the Auto Mode, the GermGuardian AC5109W automatically adjusts the fan speed to match the environment’s needs. This Smart Sensor is necessary to keep the energy costs low and, as a result, prolong the life of the air filters.

For basic features, the GermGuardian AC5109W has child lock, a timer, and an LED indicator for filter replacement.

Related posts:

1, Best air purifiers for smoke.

2, Best air purifiers for dust.

3, Best air purifiers for mold.

GermGuardian AC5109W Customer Service

There is not much to say about the brilliant support from Guardian Technologies’ customer service. Anyone can get active support from the American brand. The company also makes the instruction manuals available online to help you answer common questions on your own. But if you can’t find a solution, just contact customer service via phone at 866-603-5900 or via email at Just like any other brand, the office will be open from Monday to Friday.

Guardian Technologies occasionally offers free shipping as well as a significant discount on all products (typically 10% to 20%). Whenever you find the air purifiers are not as great as you had 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 it warrants its products to be free of defects in materials or workmanship. You can register for a warranty for up to five years.

For the GermGuardian AC5109W, you will have a 3-year warranty.

Top GermGuardian AC5109W deals right now

GermGuardian AC5109W 6-in-1 Hi-Performance Air Purifier with HEPA Filter, UV-C, and ionizer.

Strong performance with all air filter types possible. Auto Mode for dealing with allergens and viruses automatically. Energy Star rating.

Our verdict

The GermGuardian AC5109W is merely adequate for keeping up with the competition. It doesn’t even have an ambition to win, so it just tries to use the old techniques for a “more expensive” air purifier. If Guardian Technologies can’t find a better way to implement better features into its upcoming air purifiers, perhaps it’s the end for one of the biggest air purifier brands.

GermGuardian AC5109W Air Purifier: Trusted Review in 2024
GermGuardian AC5109W Air Purifier: Trusted Review & Specs

GermGuardian AC5109W Reviews and Specs (Air Purifier Trusted Reviews in 2024). ✓ Cleaning Power: True HEPA + ionizer + UV-C ✓ Value: 3.8/5 ✓Certified Review.

Product Brand: Guardian Technologies

Product Currency: USD

Product Price: 239

Product In-Stock: InStock

Editor's Rating:
  • Performance
  • Features
  • Annual Cost
  • Design
  • Price


GermGuardian AC5109W is a bit overpriced, so make sure you get it on sale.