What size room is the AC4300 good for?

It is rated for rooms up to about 153 sq ft, where it circulates the air roughly 4.8 times an hour. Larger rooms will get only partial cleaning.

Does it really kill viruses and bacteria?

The UV-C light with titanium dioxide is marketed to reduce airborne bacteria, viruses and mold spores. HEPA and charcoal handle particles and odors; the UV stage is a secondary layer.

How often do filters and bulbs need replacing?

GermGuardian recommends a new filter roughly every 6 to 8 months and a UV bulb about once a year, depending on use. Indicators on the control panel remind you.

Is it loud at the highest speed?

The top speed is rated around 40 dB, which is moderate. Most owners run it on low or medium, where it is quiet enough for a bedroom.

Can I use third-party filters?

GermGuardian says genuine replacement parts are needed to keep rated performance. Third-party filters may fit but are not guaranteed to match the filtration claims.

Does it have auto mode or a timer?

No. Controls are limited to three fan speeds, the UV-C on/off and filter and bulb indicators. There is no remote, Wi-Fi or scheduling.

Where is the GermGuardian AC4300 cheapest?

At The Home Depot, for $99.99, 27% under what the other stores charge, as of our latest check.

What do buyers say about the GermGuardian AC4300?

Rated 4.7 out of 5 from 99 ratings.

Where can I buy the GermGuardian AC4300?

5 stores we checked sell it, including The Home Depot, Amazon, Staples, Walmart, Quill.

GermGuardian AC4300 Price History: $99.99 at The Home Depot

What reviewers say

4.7 / 599 ratings

Owners rate it highly, praising quiet operation, the slim footprint and noticeably cleaner air in bedrooms. Complaints center on the modest cleaning power for larger rooms and the cost of replacement filters and UV bulbs.

What people mention

NoisePraisedOwners say the low speed is quiet enough to sleep next to.
SizePraisedThe narrow tower footprint is repeatedly called out as easy to place.
Cleaning powerCriticisedReviewers say it struggles to clean larger rooms and is best kept to bedrooms.
Filter costCriticisedOwners note replacement filters and UV bulbs are a recurring expense.
Odor removalPraisedPet owners report the charcoal filter reduces dander and litter-box smells.

From Staples

True HEPA filter captures 99.97% of allergens including pet dander, dust mites and pollen
Pet Pure antimicrobial agent added to the filter to inhibit growth of mold, mildew and odor-causing bacteria on the filter surface
Charcoal filter reduces common odors from pets, smoking and cooking
UV-C light technology works with Titanium Dioxide to reduce airborne bacteria, viruses, germs and mold spores
22" three-speed tower best for small to medium rooms, CADR rated 100+
Electronic controls include UV-C control, filter change indicator and UV bulb replacement indicator

Guarantee: Use genuine Guardian Technologies replacement parts to maintain product performance and warranty.
Returns: Free returns, online and in store, always free.
Shipping: Delivered free; free shipping on orders.

About the GermGuardian AC4300

Breathe fresh and cleaner air! This GermGuardian air purifier reduces filters odors, and traps airborne particles with a True HEPA Pet Pure filter and optional UV-C light. The Pet Pure filter tackles pet dander and reduces unwanted odors. Your at home comfort can be customized with 3 speed settings, ultra-quiet mode on the lowest speed setting, and an optional UV-C light with an easy to use control panel. This air purifier circulates the air 1x per hour in 743 square foot rooms and 4.8x per hour in 153 sq. ft rooms and is ideal for medium to large sized rooms such as: dorm rooms, bedrooms, and other living areas! Your purifier is only as powerful and effective as the filter you put inside, and our Genuine GermGuardian replacement parts are essential for maintaining product performance. Each filter or bulb is designed specifically for a particular unit style. Not only will genuine replacement parts fit like a glove, but they also have the combination technology to match so that you can get the most out of your air purifier. CADR RATING Dust (107) Pollen (116) and Smoke (99). Comes with a 3-year limited warranty for peace of mind.