Review on Germ Guardian True HEPA Filter Air Purifier with UV Light Sanitizer, Effective against Germs, Allergens, Pollutants, Smoke, Dust, Pet Dander, Mold, Odors, Silent 28in 4-in-1 Home AC5300B Air Purifier by Dawn Valdez

Purchased two (2) of these types in November 2018, one of the units began to produce a very high pitched squeak/whistle at low volume. but loud enough when you're in the room with him to ask what that sound is. The noise was starting to get annoying now that I turned off the block and stopped using it, I even went so far as to put it in another room in the house and if all is quiet and you're in another room then you can whistle a blow here. I went to the manufacturer's website to find out that they offer a 30 day guarantee and if you would like them to look at the product, send it back to them at your expense and they may be able to fix it. There is no guarantee that they will do anything about it and if they decide not to do anything, you are out of luck and have no money for the cost of the device and shipping. Today I noticed that the second device is just starting to make the whistling noise that the other is making. They work well, the dust level in the house has dropped drastically, I can say that they are working on the amount of dust left on the pre-filter. Buyer BEWARE you are out of luck with this item after the Revain return period or 30 days.