GermGuardian AC4100 Review: Cheap + UVC Sanitizer

A speaker like design air purifier with the latest UV Technology, amongst GermGuardian AC4100 long list of features, affordable price tag is arguably its main strength in this competitive small air purifier market. With a versatile body framework that is portable for its segment, is the air cleaner adaptive enough to take on other entry-level air purifiers? Hit the break to learn more.
± 89.99 p
     Annual filter ^    
± 48 - 65 p
 Online price*
** MRSP (Manufacturer's Suggested Retail Price)/ RSP (Retail selling price) is provided by cleanairprice.com. Accurate at the time of posting.
^ Annual filter cost is calculated based on filter price and 12 hours of usage. Pricing could vary depending on air quality, usage frequency, and speed.

GermGuardian AC4100 Specification

ProductGermGuardian AC4100
6.5 x 11 x 7.5 in
(16.5 x 27.9 x 19.1 cm)
Weight4.85 lb (2.2 kg)
Coverage (up to)78 sq. ft. (7 m2)
Airflow speed
Dust free (CADR)56 cfm (95 m3/h)
Pollen free (CADR)76 cfm (129 m3/h)
Smoke free (CADR)50 cfm (85 m3/h)
Humidifying(H) speed
- Lifespan
- Replacement cost ($)
Charcoal Pre-filter
6 - 9 months
HEPA filter
- Lifespan
- Replacement cost ($)
HEPA filter
6 - 9 months
Carbon filter
- Lifespan
- Replacement cost ($)
Ionizer/ Technologies
UV-light/ PCO
LB4100 UV-C Light
10 - 12 months14.99
PCO Filter
Other filter
All-in-one filter
- Lifespan
- Replacement cost ($)
FLT4100 Filter-E HEPA
6 - 9 months
Optional/ Addon
Noise level
Power usage level
Timer/ Scheduler
Auto mode
Air qualityAQ indicator
Filter change indicator
More color options
Wi-Fi/ BTBluetooth
Remote control
Child lock
Warranty1 year
Email/ Phone support

Key features

  • 4-stage filtration with 3 speed
  • Charcoal pre-filter
  • Combination HEPA Filter
  • Optional UV-C Metal Shield with Ti02

The starters

GermGuardian AC4100 dimension
6.5 x 11 x 7.5 in
(16.5 x 27.9 x 19.1 cm)
GermGuardian AC4100 weight
4.85 lb (2.2 kg)

At a mere 6.5 x 11 x 7.5 in dimension, GermGuardian AC4100 is a very compact air purifier at the size of a single speaker. The 4.85 lb weight is equally light for carrying around despite the lack of carrying handle. At the rear, you will find the air inlet covering most part of the air purifier and air outlet is at the other way round. Overall the build quality is “cheap”, but will do its job in holding everything together.

GermGuardian AC4100 controls

On to usability, AC4100 is very simple to use as there is only one front dial knob for 3 fan speed control and UV-light on/ off button. At the back, you have the Filter Reminder back wheel that requires manual adjustment. There are 4 felt pads you can stick it depending on what position you want the air purifier to operate in. Other than that, there is nothing much in it other than the 4-stage filtration and a standard 1-year warranty.

Airflow, speed, and CADR

GermGuardian AC4100 coverage
Purifying coverage
78 sq. ft. (7 m2)
GermGuardian AC4100 fanspeed
As an entry-level compact air purifier, AC4100 estimated 60 sq. ft. purifying coverage is rather poor. Probably best used in close range like desktop, bedside or next to litter tray. The 3-speed airflow delivery rate isn't any better either although that is expected given the air purifier limited performance. No official CADR but it should follow the similar low output pattern.

Recommended Read

What’s inside count

As mentioned earlier, GermGuardian AC4100 is a 4-stage filtration (3-stage officially) at a very compressed body. You have the initial carbon pre-filter that handles large particles and smoke/ odors pollutants. With those pesky particles out of the way, the HEPA filter would uninterruptedly capture smaller micron size particles at 99% efficiency. As for notorious and tricky allergens including bacteria and viruses, you have the last stage UVC-light + PCO filter standing by for the last round elimination before releasing the purified air out.

Keep it down

GermGuardian AC4100 suppose to have a very decent noise level given its low airflow delivery rate, but we find that it's rather loud at second speed onwards if you place it at desktop use. On the flip side, power consumption is low across all speed even the air purifier does not have any eco-ness technology.

At what cost

GermGuardian AC4100 MRSP/ RSP
+- 89.99
GermGuardian AC4100 annual filter replacement cost
Annual Filter Cost
+- 48 - 65
^ Replacement filters/ estimated cost
Other than the different variants from GermGuardian, AC4100 it's the only few affordable air purifier that comes with UV-C light technology. While the comprehensive 4-stage filtration is good to have, it does add up to the annual filter maintenance cost unless you want to skip the UV-C bulb. Another thing is the combination filter E set cannot be purchased separately and you have to replace it every 6 months on regular use.
No doubt Amazon has the best deal for GermGuardian AC4100 that includes free shipping with Prime and 30 days return policy. Guardian Technologies website and other retailers like BestBuy, Overstock, Walmart, Target should also be in your consideration list if you manage to find a better deal and don't mind the hassle account registration.

GermGuardian AC4100 VS the challengers

Hamilton Beach TrueAir Compact Pet 04384

Hamilton Beach 04384 TrueAir Compact Pet

Similar price range but TrueAir utilize a permanent HEPA-grade filter that will save you on annual replacement cost. purifying zone also double but the downside is a weaker filtration depth and lacks UV-light technology.
GermGuardian AC5250PT

GermGuardian AC5250PT

A much better proposal in our book with more than double of its purifying coverage, faster airflow delivery rate, 3 years warranty, and bigger, better True HEPA filter. All that for a little bit of top up.
Levoit LV-H132 Air Purifier

Levoit LV-H132

Again, spend a little bit extra, you have yourself a better air purifier with True HEPA filter, activated carbon filter, faster airflow distribution, night light mode, and cover more ground. Filter replacement cost is surprisingly lower.
Levoit LV-H126 air purifier

Levoit LV-H126

Yet another Levoit air purifier that offers True HEPA filter, single activated carbon filter, wide 161 square feet purifying applicable area and an extended 2 years warranty. LV-H126 looks much cooler and trendier too.

Final thoughts on GermGuardian AC4100

Air purifier keeps getting cheaper and cheaper every day. For such a low price, GermGuardian AC4100 has strong 73% 4-5 stars rating in Amazon that mostly focuses on its price tag, and effectiveness against dust, pet allergies. The 17% that gave 1-2 stars bad review are mostly concern about 2 things. 1) The durability where the air purifier dies with burning smell that likely coming from the circuit board. 2) It's loud. For an air purifier that supposes to place on the desktop, fan noise can be clearly heard. If you want something that is dirt cheap and does not mind the relatively short 1-year warranty, go for it.


  • Affordable for a 4-stage filtration air purifier with UV technology.
  • Beautiful speaker-like body that is compact and practical.
  • Works in vertical and horizontal position.
  • Charcoal Pre-filter that detaches from the HEPA filter for vacuuming.
  • UV-C light technology that can be turned off when not needed.


  • Below average purifying coverage and filtration strength. Uses HEPA-type filter that has "only" 99% efficiency.
  • Annual filter replacement cost is high and can cost more than the air purifier on long use.
  • No addon features like timer, Auto mode even though it is understandable given its size and price tag.
  • Uses manual filter reminder date wheel.
GermGuardian AC4100

Max Fernandez

A loving father and a dedicated reviewer for airfuji.com with more than 1000 air purifiers under his belt. Max Fernandez is also one of the million patients currently suffering from asthma. Feel free to nudge him if you have any questions.

Other Guardian Technologies Air Purifiers