GermGuardian True HEPA filter air purifier with UV light sanitizer reviews


How does UV C light help to kill the germs? UV C light helps kill airborne viruses such as influenza, staph, rhinovirus, and works with Titanium Dioxide to reduce volatile organic compounds. GermGuardian Air Purifier filters air in medium to large rooms and cover 743 sq. feet at 1 exchange per hour, 371 sq. feet at 2 exchanges per hour, 248 sq. feet at 3 exchanges per hour, and 153 sq. feet at 4.8 exchanges per hour. Should you buy it? Get more in GermGuardian True HEPA filter air purifier with UV light sanitizer reviews.

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In the box

The GermGuardian AC 4825 doesn’t come with a lot of accessories, but for the low price, I wasn’t really expecting many. The air purifier is well packaged and secure inside the branded box it ships in. Inside the GermGuardian box I found:

  • 1 GermGuardian AC4825 air purifier
  • 1 Use and Care Instructions
  • 1 Quickstart Guide

Pros & Cons – GermGuardian True HEPA filter air purifier with UV light sanitizer


  • UV-C feature kills germs
  • Carry handle built-in
  • True HEPA filter + prefilter/carbon filter
  • Easy to operate
  • Great air coverage for its price range
  • AHAM Verified & Energy Star Certified
  • Filter & UV replacement reminders
  • Low operational noise
  • White version available
  • 3-year warranty
  • Maintenance is easy to perform
  • Prefilter/carbon filter separately replaceable


  • Tall height may not be suitable for all users
  • Rotary manual control fan speed switch
  • UV-C feature has no memory feature
  • Blue glowing trim could be noticeable to some with high sensitivity
  • No auto mode or auto-off timer feature
  • You’ll need to buy 3rd party filters to save money as originals are more expensive

Specs – GermGuardian True HEPA filter air purifier with UV light sanitizer

  • Weight: 8.65 lbs
  • Cord length: 6 ft.
  • Control location: top
  • Size: 6.75 x 10.25 x 21.5″
  • Room size rating: 167 sq. ft (medium room)
  • UV-C germ killing light
  • True HEPA filter w/ activated carbon filter
  • CADR (Clean Air Delivery Rate) ratings: Dust (118), pollen (125), smoke (108)
  • AHAM Verified & Energy Star Certified
  • Low-noise fan setting
  • Titanium Oxide odor molecule remover
  • 3-speed fan control
  • Replaceable UV bulb
  • Filter replacement reminder
  • UV bulb replacement indicator
  • Dual-section blower fans
  • Simple rotary control
  • Pushbutton on/off UV switch
  • 3-year limited warranty
  • Replacement filter: FILTER B (FLT4825)
  • Power use: 55W (max. fan speed)
  • Carrying handle


With an MSRP of $150, this model is reasonably priced and in line with other efficient purifiers of the same size. It doesn’t skimp on quality and even features some of the same technology as pricier models. 

As the smaller version of GermGuardian AC5000, GermGuardian AC4825 will bring in a better price tag. You will get an under $100 air purifier with all the benefits a True HEPA air filter could do. For the same price, only Honeywell HPA060, Levoit LV-H132, AeraMax 100 and the PureZone are the most well-known opponents of this GermGuardian AC4825.

Annual Costs

Using a 5 watts UV-C bulb, GermGuardian AC4825’s power consumption is 53 watts. It is still higher than many other energy-saving air purifiers in the market, like the Blue Pure 411, Levoit LV-H132, SilverOnyx or AeraMax 100. However, this is an Energy Star air purifier, because it has very small CADR/watt rate.

For using a GermGuardian AC4825 8 hours per day, it would cost you up to $19 per year.

ModePower Use, UV-C OffPower Use, UV-C On

Compare GermGuardian True HEPA filter air purifier with UV light sanitizer vs Levoit Air Purifier

Levoit Core 300
Dust CADR118.0
Smoke CADR99.0135
Dust CADR/watt2.21
Coverage743 sq ft219sq ft
Annual Energy Use (kwH/year)304.2947368
Noise (min-max in your test)NA24db
Voice ControlNN
FilterHepa, Antibacterial, CharcoalH13 True HEPA
Fan Speeds33
Height21.5 inches16in
Replacement Filter


WarrantyLifetime Warranty1 year

GermGuardian True HEPA filter air purifier with UV light sanitizer reviews


This model features a tower design with a height of 22 inches. At roughly 7 lbs, GermGuardian AC4825 air purifier is even lighter than the CDAP4500BCA which weighs 9.45 lbs. With a relatively small size, GermGuardian AC4825 is compact and therefore easy to bring anywhere in your home.

Top panel

At the top of GermGuardian AC4825, you will find a twin control panel with AC5000E, with only one UV-light button, one on/off button, one fan speed switch and a LED filter replacement indicator.


After opening and unpacking it (which consisted of removing the corrugated cardboard inserts – styrofoam isn’t used with this one) I finally to check it out and turn it on! The AC4825 is built with a solid, good-feeling ABS plastic body and has a nice low-gloss black finish. The top features a matte silver finish with a satin black top section surrounding the controls.

There is a simple to use control pan on the top of the machine with an analog dial and a button to control the UV-C light function. The UV-C light itself is represented in a small band that runs around the bottom of the control panel, when engaged it emits a soothing blue light that is hardly noticeable even at night.

3-stage filtration

First, air is filtered through a pre-filter—an activated charcoal layer which is a special type of carbon that catches larger particles and kills unwanted odors.3 Second, a HEPA filter is used to catch fine, microscopic particles like pollen, dander, and dust. HEPA filters are expensive, but extremely high-quality because of their ability to trap minuscule particles in comparison to other standard home filter systems.2 The third and final filtration system is also what makes the GermGuardian Air Purifier quite unique. This model uses a UV-C, or Ultraviolet-C light, that kills airborne bacteria and germs that are known to cause certain allergies and diseases.

UV-C Light Filter

UV-C Light filter is the very thing that makes the GermGuardian special. In fact, it can only be called ‘Germ’ ‘Guardian’ = ‘Guardian against germs’ because of this filter.

According to GermGuardian, the UV-C Light filter ‘kills airborne germs and viruses’. As we know, ultraviolet light is a 10-400 nanometer wavelength light that’s a degree more powerful than visual light.

The GermGuardian UV-C light filter uses the very UVGI that is proven to ‘kill or inactivate microorganisms’ such as bacteria and viruses. With the UV-C light filter, the GermGuardian’s 4-stage filtration system is complete.

PECO filtration, for example, is another technology implemented by Molekule Air that similarly disrupts microorganisms. Airdog X5 uses other techniques entirely.

CADR Rating And Room Coverage

With GermGuardian, the germicidal filter is the main focus. However, we have one measure that we can compare all air purifier on, and that’s CADR rating. CADR rating primarily evaluates the efficiency of HEPA filters.

You might notice that most GermGuardian air purifiers are designed for smaller rooms. We can put the in 3 categories:

  1. Console air purifiers for bigger rooms. Example: GermGuardian AC5900W and GermGuardian AC9200W with 335 sq ft and 338 sq ft coverage area, respectively.
  2. Tower air purifiers for small rooms. Example: GermGuardian AC4825E, GermGuardian AC5000E, and GermGuardian AC5250PT with 167 sq ft, 161 sq ft, and 180 sq ft coverage area, respectively.
  3. Desktop air purifiers for the smallest rooms or offices. Example: GermGuardian AC4100 with 78 sq ft coverage area.

The GermGuardian console air purifiers have the highest CADR rating; a bit over 200 for smoke, pollen, and dust CADR. They are more capable of removing small particles from indoor air but they are also more expensive.

Tower air purifiers by GermGuardian are the most popular ones. Then have a 100+ CADR rating.

The smallest desktop GermGuardian air purifiers are very small and have a 50-80 CADR rating.

All the room sizes are calculated with 4 air changes per hour in mind. That means that all air purifiers change all the air in a room of the recommended area every 15 minutes.

Noise Levels

At its highest speed, I definitely could notice the air purifier running. Its noise level is similar to a box fan or tower fan, and though it fades into the background, it’s definitely noticeable. I recorded it at 56db.

It’s worth noting that this is a little loud for a machine of its size and capacity. By contrast, the Coway Mighty air purifier which has more than double the power and coverage area of the GermGuardian, has the same noise level on high speed. If noise is a particular issue for you, it might be worth springing for a higher-priced air purifier.

The noise level is far less than a tower fan or even a space heater. At the lowest setting, the GermGuardina ac4825 sounds like a small white noise machine or fan at its lowest setting.

How to setup?

The air purifier ships completely assembled and with its filter in place. The machine requires a filter replacement every six to eight months, but you’ll know it’s time when the machine’s indicator flashes red.

The filter is very easy to replace, but must be purchased separately at a cost of about $35. There are slightly cheaper filter options if purchased from a third-party vendor, but we recommend sticking with Guardian Technologies’ official filters as anything else can be risky if you don’t know what kind of quality you’re getting.   

Filter replacement

To remove the filter on the GermGuardian, simply press the release latch on the back of the air purifier located at the top of the machine near the control panel. Carefully remove the back of the air purifier and set it aside. Remove the HEPA filter with the charcoal filter layer, and discard as directed on the new filter packaging. Next, open the filter replacement and replace the filter cover before plugging the machine in again and turning it on.

How to replace the filter?

Filter replacement is easy and only takes a few seconds. I was pleasantly surprised by how easy it is. It’s just a few simple steps:

  1. Press down on the release tab on the rear cover
  2. Pull the cover down and out (there are 2 tabs on the bottom which rest in tab slots)
  3. Using your fingers, pull the filter out and down to remove it
  4. Replace filter using the opposite motion
  5. Insert the cover’s tabs in the base
  6. Swing the cover up and snap the release tab back in place

GermGuardian True HEPA filter air purifier with UV light sanitizer Performance reviews

According to GermGuardian themselves, the AC4825 can exchange up to 743 sq feet of air per hour. This means that in a closed room of ~750sq feet the air is being fully purified once per hour. Finding a completely closed room in your home can be difficult but with that baseline for performance, this machine is best suited for a closed room size of 153 sq ft. At 153 square feet, the GermGuardian should be able to exchange the air 4.8 times per hour, which means you are getting almost constant refreshed, HEPA filtered air every ~15 minutes.

I was excited to put these claims to the test.

With a bedroom size of 184 sq ft, this allows me to run the machine regularly at a lower fan speed and still maintain great air quality thanks to the HEPA filter. When air quality gets low during the spring or fall I can move the speed up and continue to have great air without needing to worry about longer filtration times.

The air gap in my bedroom door is actually pretty large, so even though I could expect the air quality to improve pretty quickly, it took a little longer than the ~15 minutes for the air quality to stabilize. I placed the air quality meter close to the air purifier to get a consistent reading, but I started to see some of the values fall over the first few minutes. The air quality began to level off after 15-16 minutes, at which time I felt I’d reached optimal air quality.

To begin my test I plugged the air filter in and took a baseline reading of my bedroom’s air quality with a handy digital air quality meter. While the air quality can give you a ton of information I was primarily focused on the overall air quality reading, and

Upon turning the air quality meter on, I was pleasantly surprised to find that my bedroom air quality was actually pretty good, even considering the crazy amount of pollen floating around and the amount of pet dander my two dogs create.

Next, I turned the GermGuardian Ac4825 to the highest setting, started my timer, and sat back to let the air purifier do its thing.

GermGuardian True HEPA filter air purifier with UV light sanitizer customer reviews

Clean air Plus UV!

Wife and I have been wanting an air purifier for a while but it has always been a back burner until recently! We bought two of these to run to clean the air and especially the UV for any biologicals. I am a first responder and plan on probably getting Covid-19 at some point and I want to seal myself off in a room with one of these and the other one in the other part of the house where my wife will be to help minimize her exposure. She has asthma. Anyway…

WE love these units, We picked them for the high ratings and see why. They pump out fresh clean air hour after hour and I like the blue light on the front that shows the UV is on. They are quieter than I expected but keep in mind they are a fan and the higher the setting is the louder it is. It does not interphase with tv ect. The higher the setting the quicker it pulls all the particles out of the air and replaces with fresh air! Great product by a trusted name!!! Get prepared and get one of these asap!

By Ljo1503 at Best Buy

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