Review on ✨ Optimized for SEO: PureGuardian H4810AR Ultrasonic Warm & Cool Mist Humidifier, 120 Hours Runtime, 2 Gallon Tank, 600 Sq. Ft. Coverage, Large Room – Silent, Filter-Free, SilverClean Treated Tank, Essential Oil Tray by Mona Kohkayne

After many purchases, I purchased this unit a year ago from my local Costco store for $69. It appears to be much more reliable and efficient than other $150-$200 devices. I like it, except for one issue: like all ultrasonic humidifiers, when you fill it with tap water it gives off fine white dust (which forms from natural minerals in the water). I have a water softener, a basic water filter, and a UV water purifier, so my tap water is pretty damn clean (it comes from a deep well). After operating this device with tap water for 2 days, the dust is very visible on all dark surfaces. The manufacturer sells a $20 "dust filter" that you can order online. It is conveniently screwed directly into the device. i bought one This reduced dust emissions by around 50%. I tried distilled water but it's too expensive. I then tried spring water, which I buy in 6-gallon jugs from Costco for about $7.50. This seems to have eliminated or significantly reduced the dust problem. Drive 3 days and no dust. By the way, if you have a gas stove, this micro dust in the air will make the flame burn orange. I let the unit work in the basement with the door to the upper level closed (where my oven is located) but the flame still turned orange. This slightly reduces their heat transfer during cooking. And one more thing, the design and control features of this device are great. unless there is an option "warm fog". Great idea in winter. Unfortunately that doesn't work. The mist never heats up, even on the Hi setting. If you want a warm mist, you need to fill it with hot water. It must have been designed by the same people who installed the "close door" button in elevators; they never work either. I hope that was helpful. Silver Surfer.