Humidifiers: the downsides, first

Reliability and durability are negative aspects in Amazon's review summary (durability: 101 of 142 mentions negative), with owners describing units that stopped working, tanks that cracked and leaked, and units that broke after about 1.5 years.

Wirecutter's tests found the auto mode accurate, but it has heard from readers, staff and Amazon reviewers that the humidity reading becomes unreliable over time. Resetting the unit (hold power for 15 seconds) often helps. Amazon's summary calls humidity output mixed, with some owners saying no mist comes out at all.

Wirecutter warns that, like other ultrasonics, it can leave a trail of fine mineral dust unless you use distilled or filtered water, and the base has nooks that are annoying to clean. Amazon owners are split on cleaning, with some saying there are too many parts to take apart.

Wirecutter notes the warm-mist heating element can get dangerously hot and cites the Mayo Clinic's advice against warm-mist models in homes with children. It also recommends skipping the essential-oil tray.

Leakage (200 of 227 mentions) and durability (179 of 229) are negative aspects on Amazon. Owners report water leaking from the bottom, units breaking within two months, and cracked tanks.

Wirecutter says the construction doesn't feel as durable as its other picks, the 4 L tank is smaller than they'd like, and it has no carrying handle.

Wirecutter says to use distilled or filtered water, since minerals in tap water can leave white residue or particulate matter in the air.

CNN Underscored measured an average of 34 dB and called it not as quiet as others it tested. It also has no on-unit sleep-mode button.

Wirecutter says the 0.9-gallon tank falls just below its 1-gallon guideline, so larger rooms or very dry climates will mean more refilling.

The Spruce says the wick filter costs about $30 every six months or so, and Wirecutter says it is designed for a roughly six-month replacement cadence.

Wirecutter notes its fan makes it louder than an ultrasonic model, though still well below conversation level. The Spruce reports that testers of evaporative models, including this one, wished they could see mist to know it was working.

Leakage is a negative aspect in Amazon's review summary (607 of 668 mentions negative), with owners saying it leaks everywhere. Wirecutter says Amazon reviewers and a few staffers found the tank started leaking after a few months, some pointing to the float-valve rubber stopper.

Durability is negative on Amazon (411 of 570 mentions), with owners reporting units that broke within about three months or turned off constantly.

Good Housekeeping's only listed con is a base with many cracks and crevices. Wirecutter found the area around the mist chimney and the water channel in the basin tricky to scrub. The Spruce, however, found it easy to clean.

CNN Underscored's 6 L tank lasted about 39 hours on low against Levoit's 60-hour claim, and it struggled in medium-size rooms. CNN also called the VeSync app buggy, and Wirecutter found the icon-only buttons counterintuitive.

Wirecutter says you should use distilled or demineralized water, or the mist can leave a chalky white film across the room.

Leakage is a negative aspect in Amazon's review summary (667 of 792 mentions negative), with owners saying it leaks water everywhere.

Sleepopolis flags the spill risk of boiling water for homes with children, pets or clumsy people. Wirecutter notes the Mayo Clinic recommends against warm-mist models in homes with children.

Amazon's summary calls noise mixed (some find it super quiet, others noisy) and durability mixed, with some units breaking after a month. Sleepopolis heard gurgling for a few minutes while the water boils.

Sleepopolis found the night light turns on automatically and can't be turned off, and advises shorter run times in small rooms. Reviewed's (Canada) only listed con is that it can steam up rooms.

Sleepopolis describes weekly cleaning: let it cool, then soak and scrub the heating element in white vinegar for 15-20 minutes, and disinfect with diluted bleach.

Wirecutter says Canopy's models work well but not enough to justify their extravagant price tags. Canopy says to replace the filter every 45 days ($17 one-time, or $12 per 45 days on subscription). Amazon owners call the filters expensive and rate value for money as mixed (47 of 73 mentions negative). HGTV lists the price and ongoing filter cost as its con.

Humidity output is mixed on Amazon, with some owners reporting no mist and no rise in humidity.

HGTV's tester found every setting quiet enough to sleep with except high. Noise is mixed on Amazon, where some call it very loud.

HGTV notes its anti-mold airflow keeps the fan running until no water is left, so it may run all day even when you're not in the room.

Good Housekeeping found it not the easiest to clean because of the narrow tank opening (a brush is included). Cleaning is mixed on Amazon, where some owners say it is almost impossible to clean. A Walmart 1-star reviewer says mildew builds up inside the tank, which can't be fully opened.

Reliability is a negative aspect on Amazon, citing units that stopped working after a week or won't turn on. Several low-star Walmart reviews describe units with no mist, units that arrived broken, or tanks that leaked.

CNN had to refill it every 18-20 hours on low and wouldn't use it in larger rooms. Good Housekeeping rates it up to 12 hours on high. HGTV lists frequent refills as a con.

CNN notes there is no built-in hygrometer, so it can't avoid over-humidifying. HGTV found it makes a loud water-cooler sound when the water runs low, and its display stays bright even with the night light off.

Noise is a negative aspect on Amazon (20 of 24 mentions), including clicking and rattling. Wirecutter says it's louder than its ultrasonic picks, creeping toward 60 dB on the higher settings.

The Amazon listing averages 2.4 stars from only 61 ratings. Its summary cites major engineering flaws, cheap plastic, a fan that wobbles, and units shutting off after about a minute.

Wirecutter says the wicking filter needs replacing every month or two depending on use; Vornado offers a subscription.

Wirecutter found that you must remove the whole top to get the tank out, and the handle-less tank is frustrating to carry when wet. You can fill it in place with a pitcher instead.