I purchased this unit back in January for our bedroom and have had to replace the filter once during that time. All seemed to be working well until we returned from a 2 day vacation to find that our entire house smelled of burning plastic. We quickly figured out that the burning plastic smell was coming from this air filter which had been running on the lowest setting during our 2 day trip. It was still running despite the burning smell. My husband took it apart to reveal that there were melted plastic parts inside and the circuit board was scorched. I wish I would have read the negative reviews further and will do so in the future when buying a machine that could endanger our house and family!!!

I like the function of the purifier. It runs quietly, and I immediately noticed that I would wake up in the morning way less congested than I had been without it. Cleaning and changing the filter verifies that the unit is indeed pulling contaminants out of the air as well.

I liked the unit so much that I ended up ordering two more of them over the next several months.

6 months after my original purchase, my unit started to bug out. The cable, a few inches from where it was plugged into the wall, had developed an issue. As I moved the bend of the cable, the unit would flicker off. The cable had obviously developed an open inside of it. This unit had been essentially stationary since opening, with an occasional cleaning and one filter replacement. There was no undue stress on the cable.

The product was covered under warranty. I emailed Guardian's customer support to ask about the issue. I was told that the cable was not a replaceable part, that I needed to ship the entire unit back to them, and that I would have to pay for shipping.

The exact wording in the email was, "Per the terms of the warranty as stated in the manual, the customer is responsible for the shipping costs..." The product manual doesn't state this. Using USPS shipping estimator, it looks like this will cost around $28-40 to ship back to the factory.

Guardian wants me to pay a third of my original purchase price in shipping charges in order to exercise the warranty on their faulty product. Perhaps this is their way of deterring us from exercising the warranty at all.

Buyers beware. This is how Guardian supports its products.

Although I dust & vacuum fairly often, I noticed I still had issues with my asthma when spending periods of time in my room (in particular when I slept at night). I was using my inhaler much more often than usual and I couldn't understand why my symptoms seemed worse in my bedroom. I've seen advertisements for air purifiers in the past (like the ones that claimed to blow 'happy ions' in your face) & figured they were the 'snake oil' of air filtration systems. It wasn't until nursing school when I started to learn about HEPA filters for hospitals that I realized proper filtration could be a game changer for my symptoms. I did my homework while searching Amazon and came across this germguardian purifier that seemed to have great feedback. After reading reviews & confirming the integrity of customers' feedback (Fakespot.com got your back), I decided to give this filter a go. I've had this air purifier for about 5 months now and I would buy one for every room in my house if they were a little less expensive. My symptoms aren't nonexistent but they've definitely improved and that's all I could ask for! I included a picture to show just how much stuff it filters from the air. This particular filter that I've just replaced is completely coated with a thick layer of dust bunnies (and goodness knows what else) after only a few months of use. My symptoms make total sense now that I see how much stuff gets left behind when cleaning. I'm hoping to catch this purifier during a price drop one day so that I can get more for my home & maybe even one for the office I work at. In all, it helps to have a little backup to help catch all the stuff that's been missed, especially for rooms with carpeting or tons of fabric that dust likes to hide in.

We have two cats in our 4,000 sq ft house. When my sister came from out of state, she asked if our cats ran away. She said our home had zero odor or scents, which is what I was going for.

I have two of these units and one of the next size up. The larger one sits in the doorway of the cats' restroom, one in the master suite, and one in the kitchen.

On the lowest setting, dust from the litter box is immediately whisked away and cooking odors do not linger. I prefer the manual operation to the larger unit's electronic controls. We have power outages frequently and the manual units power up as soon as electrical service is restored, but the electronic unit must be turned back on by a human.

We live in a more rural area, near large farms and constant construction; with an indoor litter box, the dust accumulation on indoor surfaces became overwhelming, even with my Roomba 650 running five days a week. (My robot picks up cat litter and hair like magic, but isn't much use with fine dust).

I've cleaned the filters on all three one time in the almost 90 days since we've had them. I knock the dust out of the pre-carbon filter and blow the HEPA filter out with an air compressor. I used to dust nearly every day, now I dust and deep clean about once a month. I've also noticed I haven't had to treat our long haired cat, who also spends a lot of time outside, for ear mites since February.

I did replace the thin pre-carbon filters with a Filtrete brand that you cut to size when I cleaned the units a few weeks ago. I'm attaching photos of the filter I removed and cleaned from the unit closest to the litter box, the before cleaning photo reflects how much dust was collected in a little over two weeks. (I attached a photo of the same filter after knocking the dust out). The other photo is of the furry bastard who throws cat litter and hair all over my house. He's shedding, but I've foiled his plans to make my life a living hell. Thanks to the Roomba and these Germguardian air purifiers, he'll have to be satisfied with annoying the crap out of me in other ways.

Ive used this to help with seasonal allergies and also to improve air quality in my bedroom. I leave this running 24/7 to assist with air quality control. It works well, the air smells great. Keep in mind that these things work best in open spaces. So if you have a house with a rooms that seems to be boxed off then you will want multiple units.

I compared this with the units from the local stores and this was the best purchase for the money.