Dreame L40 Ultra robot vacuum review

Dreame L40 Ultra: two-minute review

With its blend of impressive suction power, rotating mop pads, expert navigation and obstacle avoidance, self-cleaning ability and smorgasbord of AI and software features, the Dreame L40 Ultra is a solid hybrid vac-and-mop system for those looking to simplify their home cleaning regime. In fact, it’s one of the best robot vacuums I’ve tested.

Equipped with advanced LiDAR navigation, the L40 Ultra efficiently and very quickly maps your rooms, cleans in precise patterns and is better than average when it comes to dodging obstacles. With its ample suction power (up to 11,000Pa – up there with the highest you’ll find anywhere), the L40 Ultra handles dust, pet hair and small debris very efficiently, whether it’s on hardwood, tile or low- to medium-pile carpet. It mops exceptionally well, too.

Personally, I would always recommend opting for a robot model with a self-emptying cleaning system, especially if you have pets. Well the L40 Ultra’s dock not only automatically empties the robot’s tiny onboard bin but it washes its mops, too, and then dries them using warm air. No, it’s not the prettiest looking cleaning station in town but it is equipped with oversized water containers and a much larger dust bag than much of the competition. And that means you’ll spend less time doing maintenance.

You can read more about the Dreame L40 Ultra below but, if you’re in a rush, take it from me that this model is well worth the investment if you’re looking for a competent, reliable and mostly fuss-free hybrid bot to perform the mundane tasks of keeping your floor spaces in tip-top condition on a daily basis.

Dreame L40 Ultra review: price & availability

• List price: $1,499.99 / £999
• Launched: October 2024

Available in white only, the Dreame L40 Ultra comes with a list price of $1,499.99 / £999 (although when it first launched it was cheaper, at $1,249.99 / £899). Even though that puts it in TechRadar’s premium price bracket, I think it still represents strong value for money.

The L40 Ultra sits just below the company’s flagship X40 Ultra, which costs around $350 (£250) more, mostly because it comes with an extra laser for improved obstacle avoidance.

In terms of other brands’ offerings, it’s very comparable feature-wise to the Qrevo Master ($1,200 / £949) from Roborock (another Xiaomi-linked company), which sports roughly the same level of suction power and very similar onboard tech, including an extendable side brush arm and rear mop for precise edging.

You can buy direct from Dreame, or head to a third party retailer like Amazon. Seasonal shopping events always include strong robot vacuum deals, and the Black Friday sales can be a particularly good time to shop.

• Value for money score: 4.5 out of 5

Dreame L40 Ultra specs

Dreame L40 Ultra review: design

• Superb vacuuming and mopping features
• Full self-cleaning dock
• Large, jarring clean base

Backed by Chinese behemoth Xiaomi, Dreame is fast becoming a major player in the ever-expanding arena of robot vacuum cleaners and robot mops, and this high-end hybrid model comprising a 2-in-1 vacuum and mopping system is a sterling example of just how much attention to technical detail the company applies to its products, especially when it comes to features, navigation and onboard smarts. In fact, there are many similarities between the L40 Ultra and class-leader Roborock’s premium Qrevo Curv and S8 MaxV Ultra models, only this one’s for affordable to buy.

Before I get down to the nuts and bolts, I should address the elephant in the room – namely the size and design of the L40 Ultra’s charging dock-cum-cleaning station. This white-only model’s dock is 59cm in height, 41cm in depth and 34cm in width, and it’s clad almost entirely in plastic that attracts pet hair and dust like a cowpat attracts flies. To break up the monotony of so much white, the L40 Ultra also comes with a blingy, rose gold-tinted dustbin cover that some users may actually like. I don’t.

Moving on to the robovac itself. Let’s start with the little side rotating brush that all robot vacs are equipped with to fling any debris that sits outside of their chassis into the path of the main brush roller. In the vast majority of models the brush is fixed in position and its bristles can only stretch an inch or so beyond the machine’s bodywork, which makes cleaning right-angled corners near impossible.

Well, like some of the top end Roborock models, this one is equipped with an articulating side brush mount that pops out on an arm by a few inches so the spinning bristles can reach deep into corners. This is a game-changer because it means you might not need to reach for a hand vac to finish the job. Also, unlike any other model I’ve tested, this one’s side brush doesn’t engage when on carpet and that means its bristles will last longer and will be less likely to snag on a rug tassel or wrap itself in a wayward shoelace.

The same thing applies to the L40 Ultra’s mopping system, which uses two magnetically attached circular spinning mops on the rear that do an impressive job of keeping hard floors dust- and stain-free. Like Roborock’s flagship models, the L40 Ultra’s right-hand mop automatically protrudes beyond the chassis by several inches when the device is cleaning around chair legs and along skirting boards. But more than that, this model’s mops are automatically ejected and left behind in the base station whenever the bot is out on a vacuum-only run.

Yes, the L40 Ultra’s mops will retract when on carpet by 10.5mm, but the thinking behind this particular system is that it’s better for any carpet that the bot may need to cross en-route to a vacuum-only session to not have any mops fitted at all. And so it leaves them behind in the dock, just in case. After all, you ideally don’t want any dirty wet mops possibly touching the fibers of your favorite deep-pile rug lest they leave some unsightly marks.

Like most modern hybrid units, the L40 Ultra’s dock not only charges the robot’s ample 5,200mAh battery between cleaning sessions, it also sucks debris from the robot’s tiny 300ml bin into a much larger 2.3-liter dust bag. This should happily last a month or two before needing to be disposed of, unless, like me, you have a menagerie of hairy pets.

Because this model also mops, it has two huge water tanks – 4.5 liters for the clean water and an equally voluminous 4 liters for the dirty stuff. I should also add that this model ships with a small 200ml bottle of Dreame-branded floor cleaning solution, which you pour into a separate reservoir next to the dust bag section. This solution is then added to the water that’s pumped into the robot’s small water tank before it heads out on a mopping run. Like all similarly styled premium hybrid robot vacuums, the L40 Ultra’s mops are automatically cleaned in the station on its return and then dried using wafts of warm air.

The robot itself uses LiDAR, an RGB camera, sensors and AI to help it map and navigate around the home, and it’s one of the very best systems this writer has so far come across. Its initial mapping run was not only fast but exceptionally accurate, too. In fact, it was the first bot to accurately divide my downstairs open-plan flooring into four separate rooms where others have either joined two rooms together or made the entire ground floor one large room. Incidentally, the same LiDAR, sensor and camera set up is also used to detect obstacles, and very good it is, too. You can read more about my obstacle testing in the Performance chapter below.

One of the biggest issues I have with robot vacs is the propensity of loose rugs I have in every room, and rugs are the robot vac’s arch nemesis, especially if they’re not fixed down with some of that sticky stuff IKEA sells to keep rugs from slipping on hard floor. Well I’m pleased to report that at no time has the L40 Ultra snagged itself on any rug tassels or ruffled up any rugs while traversing them. I put this down to some extra height at the front of the unit that allows it to ride over almost any rug, no matter how thin and slippery it is. Top marks in this regard.

For some reason, most robot manufacturers still insist on producing circular bots instead D- or square-shaped models. As a result, the main suction area on this model is positioned between its two side wheels with 9cm or non-suction space on either side of its single rubber roller. This is normal for most bots and invariably why they are equipped with a side brush to fling wayward matter into the path of the suction roller. And speaking of suction, this model produces 11,000Pa of power, which is above average and more than enough oomph for hard floors and all but the deepest of carpet pile.

Unlike Roborock and a few other manufacturers that equip their bots with two rubber brush rollers that run in tandem, this model has just one 17cm roller. Nevertheless, I haven’t seen any significant reduction in dust collection as a result of having just one. As an added bonus, this model also ships with what Dreame calls a TriCut Brush, specifically designed for cutting loose hair so it doesn’t bundle together and block the main suction tube in the cleaning base when it’s drawing debris from the robot’s bin. It’s worth fitting this replacement roller if you have cats or dogs of the shedding variety.

You get ultrasonic automatic carpet detection and five levels of vacuuming power with this model – Quiet, Standard, Turbo, Max and Max+ – and a sliding scale of mop wetness depending on how dirty your hard floor is and whether it’s tile, vinyl or delicate wood. I always set vacuum power to either Turbo, Max or Max+ for full efficiency and, because I have engineered wooden floors, somewhere in the middle of the moistness chart when mopping.

Robot vacs of this nature are usually really easy to set up and this one is no different. Simply remove the dock and robot from the box, place the dock somewhere with good access to all your rooms and fill up the fresh water tank (the dust bag is pre-fitted). Next download the Dreame app (iOS and Google), tap the plus sign, select the L40 Ultra and follow the on-screen instructions. A voice assistant will chip in with odd vocal announcements during both setup and day-to-day use, and it goes without saying that this model will also respond to your own voice commands if that is your wont.

• Design score: 4.5 out of 5

Dreame L40 Ultra review: performance

• Excellent vacuum skills
• Decent mopping, too
• Impressive self-cleaning dock

The model Dreame L40 Ultra is an excellent navigator and a stalwart performer when traversing loose rugs. But how well does the L40 Ultra actually clean? Well, if the contents of the dock’s dust bag are anything to go by, I’d say it’s a winner, especially at collecting the wayward dog and cat hair that my home seems to be engulfed in.

In fact, I can often hear that reassuring whoomph sound as another cardigan’s worth of hair is being sucked out of the bot’s bin and into the dock’s larger-than-average dust bag. What’s more, this bin-emptying sequence isn’t too loud either. This, alongside the TriCut Brush feature, means I’d rate the L40 Ultra amongst the best robot vacuums for pet hair.

I have no issues to report regarding this model’s efficiency at collecting dust and debris whether it’s on my hard wooden flooring, the especially hairy carpeted rug sitting in front of my dogs’ bed or the entire floorspace of our village hall. It just heads out, cleans the edges first before embarking on systematic parallel lines for the rest of the room and then returning to its dock like clockwork. You can even adjust the frequency with which it returns to its dock to empty the bin.

I’ve been especially impressed with how well the L40 Ultra has tackled our large village hall. After mapping the 110 square meter area in about seven minutes, it then proceeded to start cleaning the edges and under any tables and chairs before sweeping the main floorspace in perfect parallel lines and what’s more, in the direction in which the floorboards were laid. Granted it seemed to skirt around three small areas for some bizarre reason but I still call it a great success.

To date, the L40 Ultra has held enough juice to vacuum the hall’s entire floorspace in one fell swoop, while in Turbo mode. That’s a remarkable statistic. It took 95 minutes to complete what I consider a huge task for any robot vac with an amazing 54% of battery power still remaining.

The same level of efficiency applies to its mopping system, which is better than any static pad-based moppers out there. No, it won’t replace a mop and bucket (or one of the best wet-dry vacuums) for rapid stain removal, mostly because it’s too much hassle commanding a robot to mop a specific area that’s only a few inches square.

By the time you’ve opened the app, selected a rough zonal area and waited for the bot to get there, you could have reached down with a damp paper towel and cleaned it up in a thrice. Nevertheless, I did perform such a test on a dried soy sauce stain and was impressed by how well the L40 Ultra dealt with it in three short passes. I put that down to those spinning mops and the downward pressure exerted on them.

Of course, the idea with robot mops is that, if scheduled, they will ensure that any hard floors are kept clean and tidy on a regular basis – and in this case right to the very edge – without any need for reaching for a wet mop, tea towel or paper toweling.

For most of my review period, I generally let the L40 Ultra use its CleanGenius method which purportedly uses AI to identify particularly grubby areas for extended cleaning. I mainly set different vacuum-only and mop-only schedules, even though the bot will happily perform both methods of cleaning during the same time frame. And as I’ve mentioned above, if performing a dual vac-and-mop function, the L40 Ultra’s mops are raised by a couple of centimeters whenever it’s crossing a patch of carpet and, if vacuuming only, it will leave the mops in the charging dock.

Obstacle avoidance is a key element when it comes to robot vacs because the last thing you want is a jammed up robot sitting there doing nothing while you’re out and about. I give this model almost full marks for obstacle avoidance, though I wouldn’t trust it with avoiding dog mess or some items below about two-inches in height.

I noticed this when I laid out an obstacle course comprising a trainer with wayward laces, a neck buff, a woolen glove, a small dog toy and a phone cable. Amazingly, the L40 avoided the trainer and its two extended laces, the neck buff and the phone wire in three different tests. However, it pushed a small soft dog toy forward on two occasions and rode over the glove, thankfully without it jamming up the suction roller.

Hence, like most robot vacs, this model is not infallible when it comes to items less than about two-inches in height. And that means I wouldn’t want to trust it with dog mess of any variety. Other than that common anomaly, I give this bot full marks for performance.

• Performance score: 5 out of 5

Dreame L40 Ultra review: app

• Easy to navigate
• Good customization options
• Could be improved here and there

While you can perform two very simple commands – clean and return to home – by tapping two buttons on the robot itself or by shouting ‘Hey Dreame, clean the kitchen’ and the like, the vast majority of setting up and customization must be done via the Dreame app, which you can download to your phone for free from Google Play or the Apple App Store.

The Dream app is very reminiscent of that from Roborock and it’s very well thought out and easy to navigate. However, there are some elements I’d like to see improved, especially zone cleaning – which doesn’t save the command for later use – and the ability to set routines along with daily schedules. That’s what I love about the Roborock app. It allows me to create a bunch of manually programmed routines and specific zone cleaning regimes and it saves them all for instant recall from the home page of the app.

On the plus side, the Dreame app lets you see the entire map of your floor plan in either 2D or 3D, and make adjustments like room merging, division and renaming, plus handy stuff like being able to add virtual walls and no-go zones. You can even select the direction of your wooden floors so the bot moves in the direction of the seams for more effective dust collection.

The app also allows you to drive the bot around the home remotely while viewing the scene from the front camera – a handy feature for checking on pets when you’re away from home. In the pantheon of robot vacuum apps I’d say it’s one of the better ones but still a little way off the wholesale customization possibilities provided by the likes of Roborock.

• App score: 4.5 out of 5

Should you buy the Dreame L40 Ultra?

Buy it if…

Don’t buy it if…

How I tested the Dreame L40 Ultra

As per usual, I spent two weeks living with the Dream L40 Ultra and noted where possible any anomalies in its cleaning patterns. Thankfully there are none to report. I also performed a number of spot checks by programming it to clean a specific dog rug and a section of hard flooring with an ingrained stain. I also took into consideration its overall performance and whether or not it fitted comfortably within a home environment.

Read more about how we test robot vacuum cleaners.

• First reviewed November 2024