Viomi Technology, a Xiaomi-backed Chinese IoT smart devices manufacturer, released its second robot vacuum cleaner. The newest device, called Viomi V2 (the full model name is Viomi V-RVCLM21B) is much more powerful and intelligent device than the first-gen Viomi robot. If you take a look at the specs and features of the Xiaomi Viomi V2 and compare it to more expensive flagship devices, you will be impressed that this model can do a lot even though it is twice cheaper than competitors. But is it really as good as it seems? We have an excellent opportunity to test this device and write our thought in this review.
Viomi V2 Highlights
- Has one the strongest suction power in the industry
- Can mop and sweep at the same time
- Has one of the biggest water containers
- Remembers your floor plan thanks to the LIDAR and SLAM systems
- Resumes cleaning after recharging in case it didn't finish the job
- The level of water leaking can be controlled in the app
- The HEPA filter is washable and lasts longer than non-washable ones. The robot is safe for asthma and allergy sufferers
- Has a great climbing ability
- Can clean a particular area when zoned cleaning has been set in the app
- Does not cross restricted zones if you create one in the app
- 2 kinds of mop cloths in the box: one is for larger areas, absorbs a bigger amount of water is only suitable for mopping; the second one is for mopping-while-sweeping needs
- 10 sensors prevent the robot from bumping, falling down and help to navigate around
- Has a short body that fits under most furniture even though the robot has a tower on top
- Great price considering the given features
Unboxing and first impression
Firstly, I want to say I love the way it looks. The combination of mint and dark grey looks very refreshing. The robot has a few mint accents: the tower is a mix of black and mint, the mopping attachment also has mint touch, the main wheel and cleaning brush are also mint. It has a fantastic dark-grey finish.
Inside the "head" there is an LDS laser that works as a scanner of a cleaning area and helps to create a map of your house.
In the middle of the body, there is a logo. One physical button works as a Home and Power button.
Under the lid, you will find a dustbin and a cleaning tool which is very convenient. The dustbin can be replaced with a water tank which is included in the box.
Underneath, there is a cleaning brush that is a mix of thermoplastic elastomer and durable nylon materials. It is solid and doesn't have detachable parts (unlike the Roborock S6 and 360 S5/S6/S7), so it is a little bit harder to clean it from tangled hair.
The rubber part of the roller is stiff, but bristles are the same as we used to see in other similar models. I believe the stiff rubber would perform better on carpet agitating more hair and debris hidden away.
Two large wheels can climb an obstacle that is up to 20 mm height and one side brush that catches debris along the walls. It has never had any issues with climbing over my door's thresholds and middle-pile carpets, unlike other cheap robot vacuums we have tested.
Mapping and Intelligent navigation
The Viomi V2 has 10 different sensors that prevent the robot from bumping, falling down and help to navigate around. The most important one which allows creating a map of your house is an LDS sensor (laser distance sensor, also known as Lidar), it is rotating and scanning surrounding with an invisible laser. Then a powerful ARM processor inside the robot vacuum process the data received from the Lidar, build a map of surrounding and the most efficient cleaning path. Thanks to the mapping feature, the robot always knows where it needs to clean and where it has already cleaned. The mapping and navigation of the Viomi are pretty good, however, it needs 20% more time for cleaning my apartment then the Roborock S6, which we have tested recently. In everyday cleaning, you will not see a difference though.
From my experience, the Viomi V2 is much better than other robot vacuums that we tested in terms of cleaning hard to reach places, for example, it covers much more narrow places on my kitchen with a few chairs and a table. It carefully moves around each chair leg avoiding collisions with obstacles without missing any spots. Also, I noticed that it is rarely bumping into furniture and walls, it always slows down when approaching an obstacle.
When I ran it the first time, the robot got confused near my bed, it made 10-15 passes around the same spot and didn't go to the dock until the battery got lower than 7%. Normally, mapping cleaners dock themselves when a battery is 20% of energy. The second time it alerted about an issue with cliff sensors on a tile where there was nothing around so we had to pick it up, check everything and place it on a floor. After these manipulations, the robot resumed cleaning. It is the first mapping robot that got confused so easily.
Why mapping matters?
The robot vacuums without mapping just run around until the battery dies. They can go over the same spots a few times leaving some areas untouched. With mapping, you can see where the robot has been and that it has covered the whole area with no untouched space left.
The Viomi 2 navigates back-and-fourth in straight lines methodically following the created map.
The Viomi V2 had to spend 47 minutes to clean 42 square meters. For instance, the Roborock S6 did the same for ~38 minutes but worth mentioning, the Roborock did a good job at optimizing cleaning path to make the robot finish the job faster.
Cleaning performance
The manufacturer claims the robot delivers 2,150 Pa of suction power, which is one of the highest suction in the robot vacuum cleaners world (most of the high-end robot vacuums have less than 2,000 Pa of suction). Why it's so important to have strong suction? If you have carpets, the dirt tends to gather inside the carpet and does not suck out so easily. It helps to pick up more pet hair, dust, and debris hidden between the carpet's pile.
We have used a digital anemometer to measure airflow velocity on the suction inlet of the robot vacuum. In our test, the Viomi 2 gets 23 CFM in powerful mode; it is one of the highest results we have ever seen and measured.
At this moment, we have seen only two models that show a little bit better result, for example, the 360 S5 and S7 reached 24 CFM in our tests. The newest (and twice more expensive) Ecovacs Deebot 950 shows approximately the same 23 CFM.
However, we tested the Viomi V2 on a middle-pile carpet on powerful mode. In one test, we scattered heavy sand on the carpet and measured how much the robot vacuum was able to pick up. Despite the strong suction, it picked up less sand than the latest Roborock S6. So it looks like the roller brush matters a lot when cleaning carpets.
When testing the robot with sand, we got to the understanding that the vacuum is not able to pick up heavy things like sand on thick carpets and when it's running on it, the sand gets deeper in the carpets and is becoming hard to get even with an upright cleaner. But let's not forget that is was extreme conditions, in everyday life you will not have 100 grams of sand scattered on carpet, right? In terms of everyday cleaning, the Viomi V2 does a good job but I would say it is more suitable for thin and some medium-pile carpets rather than for some thick carpets and is not able to provide deep cleaning on thicker rugs.
Also, the cleaning brush gets clogged with hair more than the Roborock S6 one (see the picture down below). Since the roller is not disassembled it is harder to remove hair at the edges where it gets clogged the most.
Inside the dustbin, there is a washable HEPA filter that lasts longer than non-washable ones. The robot is safe for those who suffer from asthma and allergy. When the filter is clean, the robot sucks better and overall have better performance especially on carpet.
The V2 makes about 69-76 dB of noise, the same as the Roborock S5 does. It's a bit noisy in powerful mode, but pretty quiet in energy-saving mode.
Hard floor performance and wet mopping feature
Basically, almost all the robot vacuum cleaners perform great on bare floors. Most of them are able to pick up stuff channeling it into the dustbin. The ones with mopping, however, are better because they give you an ability to wet mop your floors. For sure, this feature might not be the most helpful though it is nice not to do mopping manually.
Unlike other similar robot vacuums on the market with a wet mopping function, the Viomi V2 has a large water tank and will be suitable for much bigger houses. The 360 S5 / S7, Roborock S5 / S6 and a lot of other devices have a small 150 ml water tank attached to the bottom of the device, so those who have a big houses need to refill the water tank during the cleaning cycle which is not very convenient. The Viomi has an advantage, with the 560 ml water tank it can cover a much bigger area in mopping mode.
Another advantage of the Viomi V2 is the mopping cleaning pattern. When the Viomi is mopping, it follows a Y-shape path which is more efficient than just dragging the mop cloth around (like most of the robot vacuum do) since it goes over the same spots at least twice.
The vacuum includes two types of mopping cloths, one for light mopping and the other one for heavy mopping.
Also, there are three mopping modes in the app, you can adjust the level of water leaking depending on your needs and size of your house. It comes with two fiber cloths in the box: one is for fully wet mopping with the water tank installed, it absorbs water and is suitable for bigger areas, another one is for dampening your floors while the cleaner is vacuuming and mopping in the same time. When the unit is not moving, the water does not leak.
To start the robot mopping, insert the water tank and attach a mopping pad with a cloth. The mopping attachment is similar to the way 360 S7 water tank slides. Simply slide it underneath until it clicks. Very convenient!
The Viomi V2 has two containers when the water tank is inserted, the cleaner does not vacuum, only mops the floor but if you want the robot to do both, you can insert the mopping attachments without the tank but put a dust container inside. In this case, mopping will not be as efficient, you will need to damp the cloth over and over again if the robot is supposed to mop a big cleaning area. But this method might be good for small zones.
In terms of vacuuming bare flooring, the Viomi V2 performs perfectly. The side brush does not scatter debris too much the way other robot vacuums used to do and the cleaner picks up things on bare floor easily.
Overall, the Viomi V2 is ideal for homes with bare flooring.
Battery life
The robot lasts up to 120 minutes and if you have a big house and the Viomi will not be able to finish the job on one charge, it will automatically return to the charging dock, recharge, and resume the cleaning to finish the interrupted job. On one charge, it is able to clean 100-150 sq. meters of area.
In our test, the Viomi V2 lasted up to 88 minutes on powerful mode until needed to recharge.
App control
To control the robot with an Android or iOS smartphone, you need to download install the Mi Home app, at least if you have an international version of the robot vacuum. To use the app, you need to sign up and add your device to the app. The installation process is easy, however, I was able to connect the robot from the third attempt, for some reason, the app was not able to find the robot when I tried to pair the device first time.
Even though the overall build quality of the Viomi V2 is very good, the most frustrating thing about the Viomi robot vacuum is its app. It feels unfinished, some features just don't work, and the English localization is poor. For example, block-off zones feature doesn't work for me (the button just disappeared from the app when the map was created). Scheduling also doesn't work. Some menu tabs are not intuitive to me, things like "cleaning mode" is called "suction force" which is not really what it supposed to be.
As I understand, there are two versions of the Viomi V2 for different markets. The first one that I got works only with the Mi Home app, the second one available on the market - only works with the Viomi app. I've tried to pair my device with the Viomi app, but it was not able to find the device though I've no idea which app is more stable at the moment.
You still can use it without some useful features, and the manufacturer promises to release an update with all the glitches fixed.
When you start the cleaning for the first time, you can track in real-time how the robot scans surroundings and builds a map of your house.
The app has a few useful features:
Zone cleaning: allows you to draw a rectangle on the map and mark an area that the Viomi should clean. It's is helpful if you need to clean only a part of your room, for example, some dirty area.
Spot cleaning: send the robot to any spot on the map; it will clean two sq. meters area around this spot.
Wet mopping: in this mode, the Viomi V2 moving back and forth with Y-shaped cleaning path.
Selected room cleaning: You can select a specific room (or a few rooms) on the map that needs to be cleaned.
Edge cleaning: in this mode, the robot goes along walls and cleans corners and edges.
Block-off zones: just don't work for me at the moment, hope it will be fixed in the further app update.
In the app settings:
- you can watch a cleaning history;
- control the robot like a radio car;
- switch off/on voice prompts and increase or decrease the robot's voice volume;
- switch between three suction power modes (energy saving, standard, and powerful mode);
- change the water supply speed.
Unfortunately, the app stores only one map, so if you have a multi-floor house, take a look at the robot vacuums that can store a few maps, such as the 360 S5, Roborock S6, 360 S7 or more expensive Roomba i7/s9, Neato Botvac D7, Ecovacs Deebot Ozmo 920/950.
Price & where to buy the Viomi V2
The Viomi V2 (Pro version) so far is available to buy on Aliexpress for $472.50
Conclusion
The Viomi V2 has a great build quality, one of the strongest suction in the industry, intelligent navigation, and mapping. It cleans carpets and hardwood floors pretty good, but not as good as the Roborock S6 and 360 S7 which we’ve tested recently. My favorite thing in this device is its amazing mopping feature. I think it's one of the best mopping robots that is 2-in-1 (vacuum & mop) on the market. Considering the large water tank and special Y-shaped mopping cleaning path, it is probably among the best robot vacuum and mop in one device.
But it has one annoying disadvantage - the app, it has a few glitches, and a lack of advertised features, the English localization is bad. If the app issues will be fixed by further updates, it will be a very good device for the price that can compete with other high-end intelligent robot vacuums on the market. Even with the glitches of the app (which I hope will be fixed), it is still a very good device for the price.
Update, Oct 18, 2019: the new version of the app and firmware were released with a bunch of improvements and bug fixes. Now the Viomi V2 can recognize your rooms, and you can send it to clean a specific room. I would not say that the new version of the app is perfect, but it's much better now.
If you will not be annoyed with cleaning the brush from hair (I don't have pets but my hair is long and for me, it is a bit challenging to untangle the brush), the Viomi V2 would be right for you.
Overall, the Viomi V2 is good for those who suffer from an allergy or asthma, homes with bare floors mostly, thin carpets and one level-houses.