DREO HM524 Review: A 6L Top Fill Humidifier with Auto Mode
DREO's HM524 is a 6L top fill cool mist humidifier with a humidity sensor and auto mode, up to 60 hours of runtime and coverage up to 500 sq ft.
By Daniel Brooks
Updated October 31, 2026
The DREO HM524 6L Humidifier is a 6L top fill cool mist humidifier with a humidity sensor and auto mode, a 300 ml per hour output for up to 500 sq ft and up to 60 hours of runtime. For more models, see our Humidifiers page.
Our Verdict
The HM524 is one of the best values in humidifiers. You get a big top fill tank, a sensor with auto mode and quiet 28 dB operation at a price usually reserved for basic units.
There is no app or Wi-Fi. If you want remote control or schedules, DREO’s smart 6L model costs a little more.
DREO HM524 6L Humidifier
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Key Specifications
| Feature | Specification |
|---|---|
| Brand | DREO |
| Model | HM524 |
| Tank | 6L |
| Coverage | Up to 500 sq ft |
| Output | 300 ml per hour |
| Runtime | Up to 60 hours in sleep mode |
| Noise | 28 dB |
| Sensor | 5 percent accuracy, auto mode |
| Fill | Top fill |
Design
The 6 liter tank fills from the top and runs up to 60 hours in sleep mode, so one fill covers several nights.
Dual inlets and a wide nozzle push the cool mist up to 40 inches high, and the ultrasonic system makes a fine mist that spreads evenly.
Controls
The sensor reads humidity up to 6 feet away with 5 percent accuracy, and auto mode adjusts output to hold your target.
The ambient light changes color to show humidity at a glance or can be switched off, and an aroma function takes essential oils.
Placement Tips
Set the humidifier on a flat, water-safe surface at least a couple of feet off the floor if you can, and aim the mist into open air rather than at walls, wood furniture, curtains or electronics. Keep it a few feet from the bed or crib so moisture spreads through the room before it reaches you.
Check the room with a hygrometer for the first few days. Most homes feel best between 40 and 60 percent relative humidity, and if windows start to fog or the room smells musty, turn the output down or let the auto mode hold a lower target.
Running Costs and Care
Running costs are low: a humidifier uses far less electricity than a space heater or air conditioner, and the main extras are water, any filters or wicks, and cleaning supplies. Warm mist models use more power than cool mist or evaporative units because they heat the water.
Empty and dry the tank when you can, and clean it at least once a week so bacteria and mold do not build up. Distilled or filtered water reduces white dust from ultrasonic units and slows scale in every type. Before storing it for summer, clean and dry every part.
How It Compares
Against the Levoit Classic 160, the DREO has more than twice the tank and adds a sensor, while the Levoit is smaller and simpler.
Against the DREO HM311, the HM524 has a larger tank and a sensor with auto mode.
Pros and Cons
| Pros | Cons |
|---|---|
| 6L top fill tank | No app |
| Sensor with auto mode | Cool mist only |
| Up to 60 hours runtime | Runtime quoted in sleep mode |
| 28 dB operation | Tall mist needs clear space |
| Strong value | White dust possible with hard water |
Who Should Buy It
| Who Should Buy It? | Who Should Look Elsewhere? |
|---|---|
| Bedrooms | Smart home users |
| Nurseries | Warm mist fans |
| Budget buyers | Whole house needs |
| Plant corners | Hard water without filtration |
For more options, see our picks for the best top fill humidifiers and the best DREO humidifiers.
To see how it ranks against similar models, read our best dreo humidifiers, best ultrasonic humidifiers and best 6l humidifiers.
Final Verdict
The DREO HM524 6L Humidifier is a big-tank top fill humidifier with auto mode that offers a lot for the money. You can check the current price and details for the DREO HM524 6L Humidifier.
Frequently Asked Questions
How much space does the DREO HM524 cover?
Up to 500 sq ft.
How long does it run?
Up to 60 hours in sleep mode.
Does it have a humidity sensor?
Yes, with auto mode.
How loud is it?
DREO rates it at 28 dB.
Does it have an app?
No, it uses on-unit controls.
About the author
Daniel Brooks is a home cooling editor at WikiCooling, covering window, portable, through-the-wall and mini-split air conditioners, fans, and dehumidifiers. He researches cooling capacity, energy efficiency, noise levels, installation requirements, and buyer feedback to help homeowners choose the right unit for their room size, climate, and budget.