The Levoit LV600S Smart is a 6-litre hybrid humidifier that produces both ultrasonic cool mist and warm mist and can regulate itself with a built-in humidity sensor. Wirecutter, which names it its top pick, kept a room at a consistent 55% humidity for three consecutive days and called it one of the very few ultrasonic humidifiers it has tested that can self-regulate. TechGearLab measured a 25% rise in humidity in one hour with both modes at full power, but also recorded 44dB average run noise, under 21 hours of runtime at full output, and found the base fiddly to clean.
Full review
Humidification output
TechGearLab scored the LV600S Smart 9.5 out of 10 for humidification, the highest sub-score in its review. With warm and cool mist both running at full power, humidity in its test lab rose 25% in one hour, from 40% to almost 65%; the lead tester compared walking into the room to stepping into a tropical rainforest.
The outlet called that more humidity than most rooms need, but said it makes the LV600S Smart its best option for large spaces, with power-level control and an auto mode to keep output in check.
Self-regulation and app
Wirecutter's case for the LV600S rests on its sensor. In its tests the humidifier held a consistent 55% humidity for three consecutive days, and Wirecutter described it as one of the very few ultrasonic humidifiers it has tested that can self-regulate, where most similar models need constant watching to avoid over-humidifying a room.
TechGearLab found the VeSync app surprisingly useful: it sets timers, schedules and a target relative humidity, and includes a plant-care feature that adjusts humidity to the plants in the room. The humidifier also works without the app.
Filling and cleaning
Wirecutter notes that the top-filling tank sits flat in the sink, the lid simply lifts off, and the tank has smooth edges and an opening large enough to fit a hand inside. It still tells owners to take the unit apart, rinse it and air-dry it at least once a week.
TechGearLab rated ease of cleaning 6.0 out of 10, average for its test group. It liked the wide tank mouth but found the base annoying: a good number of small parts have to be removed for access, clearance around the vapor tower is tight, and the boiling plate has small channels that take time to clean.
Noise, runtime and running cost
TechGearLab measured 44dB average run noise, which it called a little on the high side. In cool-mist mode it heard only a small fan; steam mode starts with a low rumble like a muffled kettle and settles into a continuous low hiss. Sleep mode turns the display off but does not lower the noise.
At full output the 6-litre tank lasted 20.6 hours in TechGearLab's test, and almost 36 hours with cool mist alone. The outlet estimated about $170 to run it for roughly a quarter of the year, most of that from the energy used by the boiler, and said ultrasonic-only mode is about ten times cheaper to power.
Strengths
- +Very powerful humidification: TechGearLab measured a 25% rise in room humidity in one hour
- +Held a room at 55% humidity for three consecutive days in Wirecutter's tests
- +Warm (steam) and cool mist options
- +Top-fill tank with a wide opening, a handle and a flat bottom that sits in the sink
Watch-outs
- −Needs frequent refills at full output: TechGearLab measured under 21 hours
- −Not very easy to clean: TechGearLab found a good number of small parts to remove in the base
- −44dB average run noise is on the high side, TechGearLab found
How it compares
The LV600S Smart is the only humidifier on this page with both warm and cool mist. Its 6-litre tank is smaller than the Dreo HM735S's 11 litres, and TechGearLab measured under 21 hours of runtime at full output, against the up to 100 hours Dreo claims at low settings. Unlike the dial-only Frida Baby 3 in 1 XL, it can hold a target humidity through its sensor and app.
Rating sources
“The LV600S is the rare ultrasonic model that does everything we want: It’s powerful, quiet, and easy to clean, and it won’t over-humidify your room.”
Counts as 4.09/5 in our score — this publisher's 138 scores on the site average 3.66, so its scores are adjusted up to compare fairly with other publishers.
Our 4.1 score is the average of the 1 scored review above, each adjusted for how strictly its publisher scores; 1 more reviewed it without printing a score and is not in the average. More about methodology.
