We may earn a commission from links on this page.
The Dreame L40 Ultra is a high-priced robot vacuum that’s worth considering if you can get it on sale. I’ve had real hit-and-miss experiences with Dreame robots over the last year. I was impressed with the L10, a value model that had a lot of high-end features for the price. But the L20, a higher-priced model, was a disappointment. I was also wildly underwhelmed by the A1, which I could barely get to function. While there are better robots at the original price of this model ($1499.99, but on sale now for $1049.99) I don’t think it’s a bad buy.
The L40 Ultra only comes in white; if you need a black machine you might consider the similar Dreame X40 Ultra. The L40 has one of the tallest docks I’ve encountered at almost 24 inches tall—if you want to tuck your docking station under a counter or in a cabinet, this height can be problematic. The water tanks for the L40 are substantial enough that I didn’t have to change the water after each run.
At almost 24 inches tall, the Dreame station towers over previous docking stations.
Credit: Amanda Blum
Magnetic brushes and easy setup
On the robot itself, the most notable feature is the magnetic rotating mop heads. Instead of clicking into place, the robot activates the magnet when ready to leave the dock. Otherwise, the robot disengages the brushes so that it can better clean and wash them. This is a new trend, and I have to say, it made me worry that the robot would drop the brushes, but it never did. One of the brushes is also attached to a sweeping arm, meaning the brush extends out from under the robot to get up against walls. The robot has one roller and the same three-pronged sweeper you see on most robots.
This was a pleasure to unpack—the station was almost entirely put together, and the robot needed almost nothing to start working immediately. The Dreame app found the robot instantly—it paired to wifi on my second try after a timeout, and from then on, had zero problems.
Smooth navigation
The L40 Ultra uses LiDAR, which is now industry standard, and as such, barely needs to traverse the room to map it. Although the robot took a 15-minute tour of my home, the map was almost flawless within the first few minutes. Maps can be customized by combining or splitting the spaces that the robot perceives as rooms. Like many other contemporary robots, the L40 does not allow you to save “zones,” but you can set them for a one-time run. To effectively save a zone you have to designate it as a “room,” but this is true on most robots these days.
The robot had no problem under couches or tables, successfully navigating in and out from under them repeatedly. It struggled a bit when I sent it to a zone from another part of the house, rather than starting at the dock, and gave up. This happened over and over, and eventually I reached out to support; they were not able to successfully troubleshoot the problem. When you send the robot from the dock, it could reach any location without trouble; it only struggled going from another part of the house to a new job without stopping at the dock first.
The L40 Ultra is a champ at vacuuming
The L40 never struggled or got stuck. The wheels were a little more rugged, so even when the edge of a rug was rolled back, the robot rolled over it and proceeded. As a vacuum cleaner, the robot really excelled, getting surprisingly close to objects in the room. My white tile looked flawless, and my rugs were perceptibly cleaner afterwards. The L40 nestles right up the baseboards, so there wasn’t the familiar three-inch band of debris around the room that other robots have left behind.
On carpet, the L40 continued to be undeterred, sweeping up small debris like dust bunnies and more problematic debris like hair ties. In either case, it didn’t get held up. The L40 doesn’t love big debris, but it doesn’t get caught in the rollers; the Dreame simply avoids it. This includes pet-toy fluff and errant socks, both of which other robots would attempt to vacuum and get stuck on. The L40 never once got caught on a cord, either.
Of course, the L40 is a self-emptying vacuum, and I didn’t have to manually clear it once during my test period. The docking station did a fine job evacuating everything from the vacuum.
Mopping is a little disappointing
On the left, muddy pawprints before mopping, and after three passes with the L40 Ultra.
Credit: Amanda Blum
Something Dreame does differently from other brands is allowing the robot to vacuum and mop at the same time instead of consecutively (although you can elect that as an option, too). I found letting the robot handle both jobs at the same time the most effective, but this brings me to my top disappointment in the Dreame: It only did an okay job mopping.
We’re in peak muddy pawprint season here in the PNW, and as such, my white tile is assaulted by mud nine to 10 times a day. I had very high hopes because of the rotating mop heads and the ability to determine how much water the robot uses or how many passes it makes.
In its favor, the L40 makes very predictable patterns while cleaning, tracking the outside and then moving in parallel lines. With one pass, however, it did little more than smear the mud around. With two passes, it would still leave tracks in the middle of the path, where mud was the heaviest, but did a slightly better job on the exterior of the track. After three passes, you could barely make out the tracks, but they were still there. And this was using the wettest setting, which leaves a considerable amount of water on the floor.
I wouldn’t say the mop was a total failure; it saved me from having to get up and mop 10 times a day. If, perhaps, you are cleaning up a juice spill, the robot would do a fine job. But I don’t think muddy pawprints are outside the realm of expectations for a robot floor cleaner. The L40 did a similar job on regular grime from walking around on my wood floor and tile. It cleaned somewhat, but didn’t seem to get up what a scrub with a mop might.
One more note about the robot rushing to clean up a spill: The L40 takes a minute or two to get the robot ready to deploy for a job; if you’re in a rush, you would likely not wait around and likely handle the problem yourself.
A largely hands-off experience with some room for improvement
The L40 Ultra is currently on sale for $1049.99, and the Roborock S8 Pro Ultra, one of my favorite models, is on sale for $899.99. You’d think it would be easy to say “get the Roborock instead,” but the Dreame has a few things going for it. First, I like how rarely I had to refill those water tanks. I think the magnetic mop pads get much cleaner than the traditional pads the Roborock was using in the S8 Pro Ultra. The extending brush and pads on the Dreame get closer to the walls than the Roborock would. In Roborock’s favor, I think the singular mop pad still did a better job mopping, and it does a better job navigating spaces away from the dock.
If mopping is that important to you, you should go with a higher-end model like the Roborock S8 MaxV Ultra, which is priced at $1599. But for $1000, I think the Dreame is still a pretty decent value for most families. Stubborn stains will still require some manual labor, but the L40 will mostly take care of itself, with little intervention needed.
