GermGuardian AC4820 Air Purifier: Trusted Review & Specs

Who knew the low-end could be so good? Especially for Guardian Technologies, as they have a series of low-end air purifiers with UV-C light and high efficiency. GermGuardian AC4820 is one of them, which is shadowed fully by its successful brother GermGuardian AC4825. Today, we will have a proper GermGuardian AC4820 Review.

GermGuardian AC4820 ranks C+ in our air purifier ranking list

If you looking for higher efficiency, the GermGuardian AC4825 and GermGuardian AC5250PT are your best bets.

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 ac4820 review

  • Low-end price but great value
  • Ozone-free
  • Energy Star rating
  • 3-year warranty

  • Quite noisy at highest setting
  • A bit more expensive than AC4825
  • No additional features

Guardian Technologies has made the GermGuardian AC4820 as a ozone-free backup of the most popular GermGuardian AC4825 of the family. But does it work? We will find out quickly in our today GermGuardian AC4820 Review.

Other GermGuardian’s Air Purifier Reviews:

GermGuardian AC4820 Price

After all the glory the GermGuardian AC4825 has brought to Guardian Technologies family, the eventual unveiling of the GermGuardian AC4820 as the 100% ozone-free air purifier turned out to be less of a sensation than some had expected.

However, it isn’t simply an AC4825 without the signature UV-C light filter. But guessing from its appearance, there’s no way you can separate one from another. That’s why we need our in-depth review to know the differences.

Back to the price, our today GermGuardian AC4820 has increased to $129. Again, you can follow our link to get this air purifier with as low as $89.

Besides the common alternatives from Guardian Technologies like the GermGuardian AC4900CA or GermGuardian AC4300BPTCA, there are lots of competitors at the same price point. The Airthereal APH260 and Levoit Vital 100. For a classic product like GermGuardian AC4820, it is reasonable for you to not choose it.

Top GermGuardian AC4820 deals right now

Germ Guardian AC4820 22″ True HEPA, full room, gray filter air purifier for home.

Classic design, a GermGuardian AC4825 with no UV-C light filter. CARB and Energy Star rated.

Related post: Best air purifier 2022.

GermGuardian AC4820 Design and Size

There’s nothing exciting about the GermGuardian AC4820 design and size. It is just the pure 22-inch GermGuardian AC4825, which everyone can make mistake when looking from the outside.

germguardian ac4820 review

Source: Amazon

There is no white version available for only the best seller of Guardian Technologies family, so if you see a white one, it is definitely the AC4825.

The GermGuardian AC4820 runs the same back-to-front air flow system concept just like any other members. The front air outlet is made of perforated holes, but mainly for aesthetic, not for increasing efficiency.

You get a similar top control panel from predecessor, with a knob and a Filter Reset button. The classic models of GermGuardian is meant to be simple to use, right?

For the weight, GermGuardian AC4820 is only 8.5 lbs, and you can move it easily with the convenient back handle.

Related post: Best air purifiers for bedroom.

GermGuardian AC4820 Filters

As I said earlier, the GermGuardian AC4820 follows discretely with the old product line like PureGuardian AC2200CA or PureGuardian AP2800CA, without UV-C light filter. That’s why it just uses the simple 2-stage air cleaning system as below.

  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 – GermGuardian AC4820 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.

But don’t worry, GermGuardian AC4820 still keeps the same performance as its brothers in trapping ultra-fine pollutants. I made a test for this device in the same room of 100 square feet, and under 1 hour to help you clearly see the result. Yes, our today GermGuardian AC4820 can trap 99.9% any particles down to 0.3 microns, which is just the same as GermGuardian AC5000 or GermGuardian AC4825.

germguardian ac4820 review

We still use the FLT4825 filter B for this GermGuardian AC4820, which costs you $34. Remember to change the air filter every 6-8 months for optimal performance.

Related post: Best air purifiers for allergies.

GermGuardian AC4820 Room Coverage

As a 22-inch tower air purifier, the GermGuardian AC4820 has the similar room coverage as its brothers, to be used in rooms of only 158 square feet.

The ACH of GermGuardian AC4820 is 4X. A signature GermGuardian air purifier will clean your room 4 times per hour.

The CADR of GermGuardian AC4820 is 112 Dust/ 102 Smoke/ 131 Pollen (cfm).

Related post: Best large room air purifiers.

GermGuardian AC4820 Sound

Well, we have an “ultra-quiet operation” air purifier from Guardian Technologies. But the company still doesn’t officially state the noise level of the device, so I believe this air purifier won’t be better than any classic air purifiers from the same manufacturer.

The noise level of GermGuardian AC4820 ranges from 40 to 55 decibels (db), depending on the fan speed. If you want to keep it using in bedroom, you should switch the fan power to lowest.

Related post: Best air purifiers for baby.

GermGuardian AC4820 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.

GermGuardian AC4820 has a very good power consumption, which is only 42 watts compared to 53 watts from GermGuardian AC4825. The CADR/watt rate of this air purifier is also higher, which proves its Energy Star rating worthy.

For using a GermGuardian AC4820 8 hours per day, it would cost you just $15 per year.

Related post: Best air purifiers for pets.

GermGuardian AC4820 Additional Features

Just like the GermGuardian AC4825, GermGuardian AC4820 doesn’t have any additional features to show off. It only has one LED indicator for filter replacement, which is nice to have. One again, we must remind you that this air purifier is superseded by the latest GermGuardian CDAP4500BCA long ago, and the new device has all the Smart features you want.

Related posts:

1, Best air purifiers for smoke.

2, Best air purifiers for dust.

3, Best air purifiers for mold.

GermGuardian AC4820 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.

For the GermGuardian AC4825, GermGuardian AC4900CA, GermGuardian AC4300BPTCA and GermGuardian CDAP4500BCA, you will have a 3-year warranty.

Top GermGuardian AC4820 deals right now

Germ Guardian AC4820 22″ True HEPA, full room, gray filter air purifier for home.

Classic design, a GermGuardian AC4825 with no UV-C light filter. CARB and Energy Star rated.

Our verdict

Since the GermGuardian AC4825 is certified by the California Air Resources Board (CARB) to be safe of ozone emission, and its price has dropped under $79, the idea to have a GermGuardian AC4820 is quite redundant.

  • Performance
  • Portability
  • Features
  • Power Consumption
  • Price


GermGuardian AC4820 ranks better than its famous brother.