Roborock S4 Review

UPDATE – The Roborock S4 has been discontinued. Its nearest replacement that’s still sold is the Roborock S4 Max.

The Roborock S4 was just released. But how does it perform and is it worth the money? Let’s find out now.

Pros

• Updated drive-train with reverse capability to eliminate object or furniture entrapment
• App abilities allow for “No-Go zones” or specific spot cleaning
• Excellent cleaning performance, 96% across all of our tests
• Sweet spot between performance, usability, and price

Cons

• Does not include mopping mode and attachment like Roborock S5 and S6

Note on Models & Names

Roborock’s model and naming process can be hard to decipher. So it’s easier to understand, we created a handy guide to clear up any confusion. To learn more about the model and naming process and get the correct option, check out the Roborock review and comparisons here.

Roborock S4 Design

The design of the Roborock S4 is similar to the prior models, the Roborock S6 and Roborock S5. It includes a small bump out on the top which houses the navigating sensor.

To control the robot vacuum, there are buttons on the top as well for easy access, even if the vacuum is in motion.

Unlike other models, the Roborock S4 is only available in one color, black gloss.

What controls are on the top?

Keeping with the familiar design of the other models, the S4 has two buttons that control the unit.

These are located towards the front of the vacuum on the top, easily accessible whether the vacuum is in use or on the charger. Similarly, the laser navigation system is still in the center of the vacuum, behind the control buttons.

Here is how the buttons are used to control the robot vacuum:

• Power on / off (hold the power button)
• Start / pause the current cleaning cycle (press the large power button)
• Send to charger (press the home button)

What’s on the bottom of the vacuum?

The bottom of the vacuum has been revamped since the Roborock S6 model was made. 

What stayed the same?

Similar Features

• Edge sensors: to prevent the vacuum from “driving” off edges like stairs (The S4 has been upgraded to 11 total edge detecting sensors).
• Contact sensors: intelligent feature that communicates to the vacuum that contact has been made with the charging station and it is charging properly.
• Spiral main brushroll: centrally located in the middle of the vacuum with bristles for agitating and collecting debris directly into the cleaning path (The S4 now has a floating brushroll to adapt to changing floor heights, like going from hardwood to carpet).
• Wheels: there is a small steering wheel in the front of the vacuum used to maintain balance and 2 large wheels for navigating over obstacles (up to 2cm).

There are some notable upgrades in the Roborock S4. 

The S5 model came with a 3-legged soft bristle side spinning brush, which is pretty standard for most brands of robot vacuums we’ve tested. The S6 saw an upgrade to 5-legged rubberized sweeper without bristles.

The S4 model has the same rubberized sweeper, but now it adapts its speed. It accelerates when cleaning along corners but slows down when out in the open to reduce debris being dispersed around the room.

We noted similar cleaning performance in both the S6 and S5 models last time, even with the upgrade in the S6.

See our Roborock S5 review here and Roborock S6 review here.

Our cleaning results of the S4 were similar on hardwoods, slightly better on low pile carpet, and notably better on high pile carpet compared to the S5 /S6. While it lacks a few features, most notably mopping, the solid cleaning performance means it’s a great value.

Continue below for our extended cleaning tests and data.

Cleaning Modes

Unlike the S6 and S5 models, the Roborock S4 does not have mopping abilities. This means there are only 4 cleaning modes instead of five.

Still, it allows for a customized vacuuming experience, regardless of floor type, so it can be used in the whole house or apartment:

1. Standard mode: Use for standard multi-surface cleaning from hardwoods and low-pile carpet to high-pile shag carpets. The updated features and powerful suction power are great whether you’re vacuum hard or carpeted surfaces.
2. Silent mode: A great option when a quieter decibel level is needed, Silent Mode isn’t truly silent, but it’s notably quieter than the other cleaning modes.
3. Turbo mode: When needed, Turbo mode provides maximum suction power.
4. Medium mode: Medium mode is a suction power mode between standard and turbo.

Size & Dimensions

Compared to other available robot vacuums, the Roborock S4 is similar in size, weight, and height. Here are the S4’s specific dimensions:

• Diameter: 13.8″
• Height: 3.5″
• Weight: 8 pounds

Accessories & Parts

The Roborock S4 comes fully equipped to get started right away using the robot vacuum.

All initial accessories and parts are included in the box, with minimal assembly required. Depending on your needs, some accessories may not be used or needed.

What’s in the box?

Here is a list of everything included in the box with the Roborock S4:

• Charging station: provides a centrally located place for the vacuum to recharge between cleaning cycles
• Cleaning tool: used to maintain optimal performance, clean out the crevices of the vacuum between cleaning cycles
• Spiral brushroll: the main cleaning component used to agitate and collect debris on all floor types, even high-pile carpets, spinning constantly as it moves along the floor surface. Only includes 1 spinning brush (no replacement).
• Dust bin: houses dry dirt and debris captured as it moves along floor surfaces during cleaning cycles
• HEPA filter: washable and reusable filter located in the dust bin that traps pet dander, dust, mold and other particulates while cleaning. 1 HEPA filter is installed and 1 replacement is included.
• User manual: information on use, care, and troubleshooting the Roborock S4 is included in the user manual

RELATED – Want to see other robot vacuum reviews? Check out more here

Roborock S4 features

The Roborock S4 is on par with other high-end robot vacuums, with upgraded features for a satisfying cleaning experience. 

Though it doesn’t have the mopping feature like the S5 and S6 models, it still packs some nice features.

Let’s take a look at what’s included in this model:

App Control

The wifi-enabled S4 connects to both the Roborock and Mi Home Apps, allowing for easy control from any smartphone. We used the Roborock app in our tests.

Use the app to:

• Start / stop a cleaning
• Send the robot back to the charging base
• View digital map
• Draw “No Go Lines” for custom boundary cleaning
• Establish zones or send the robot to a particular spot

Smart Navigation & Mapping

The Roborock S4 includes laser precision accuracy in its navigation system. It scans the room at 300 revolutions / minute, using that information to map out each room’s dimensions to +/- 2 cm.

The app allows you to name specific rooms so the S4 can automatically recognize a room. A schedule can also be created using rooms names.

When cleaning, the S4 uses a Z-shaped pattern around the edges before cleaning the rest of the room in a zigzag pattern.

As the S4 cleans each room more and more, algorithms work to create a more efficient cleaning path with less chance of missing spots.

Cleaning maps called “digital map reports” are generated and viewable. It’s easy to see where the robot cleaned and if any spots were overlooked.

Recharge & Resume

This feature is similar to one used by Roomba robot vacuums. It ensures a thorough clean each time, regardless of battery life.

The S4 will vacuum around the room until it detects the battery getting low. When it does, the vacuum will automatically return to the charging station, stay there until fully charged, and then resume the cleaning cycle where it left off.

This is a great feature especially in large areas, reducing missed spots and uneven cleaning.

No-Go Zones

Use the app to tell the Roborock S4 where cleaning is not needed and to create virtual barriers.

You can choose a “No-Go Zone” for any reason, whether an entire room or just a specific area in a room. The S4 will avoid that section, just like the S6 model.

This is a feature also found on the Neato Botvac D7 Connected.

Cleaning Performance

To be able to make a fair assessment on cleaning performance, we do testing at both the Modern Castle lab as well as high-traffic areas of my personal home.

We use three types of floors:

• Hardwood floors
• Low-pile carpet
• High-pile carpet

We spread the following items along each type of flooring to test the vacuum cleaner:

• Rice – 0.5 ounces
• Dry Cereal – 0.5 ounce
• Kitty Litter – 0.5 ounces
• Sugar – 0.5 ounces

We use an engineered hardwood floor as our base test. Low-pile and high-pile carpet inserts are laid over the hardwood floor to do the carpet testing. Debris is scattered over each type of floor covering one at a time.

We use the same vacuum cleaning process to test all our vacuum cleaners. This creates a true to life real world, consistent and fair atmosphere to provide the performance assessment.

Here is the procedure:

1. Measure each type of testing debris by weight
2. Create a debris field in the testing lane by spreading the respective debris type.
3. Run the vacuum cleaner over the testing lane and debris.
4. Run a high powered vacuum over the test lane to remove any debris left behind
5. Empty and weigh any debris that we were able to remove in step 4

RELATED – See our other robot vacuum reviews here.

Roborock S4 Cleaning Data

Here’s the data from our Roborock S4 cleaning tests.

Hardwood Floor Cleaning

Unsurprisingly, hardwood floor cleaning performance was excellent. The Roborock S4 removed 99% of all debris in our hardwood floor cleaning tests.

This is effectively the same as we saw on our Roborock S5 and S6 tests.

The only slight issue we saw was a few debris that got left in the corners. However, these debris were not significant enough to trigger a weight on our scale.

Low-Pile Carpet Cleaning

Our tests on low pile carpet were also quite good. The Roborock S4 removed 93% of all debris.

This is actually slightly better than what we saw on our Roborock S5 and S6 tests (which removed 91% and 85%, respectively).

In any case, a 93% is a solid score in its own right.

The only debris that got left behind was a fine mix of sugar and kitty litter.

High-Pile Carpet Cleaning

Our tests on high pile carpet were actually a bit confusing. Typically on robot vacuums we see the best results on hardwoods, with waning results on low pile carpet, and then the worst results on high pile carpet.

However, the S4 removed 97% of all debris on our high pile carpet test. This is significantly more than the Roborock S5 and S6.

While the S4 does have a few upgrades over the S5 and S6, it’s our understanding that raw suction power isn’t among them. As a result, we will probably look to re-do our S5 and S6 tests to ensure those robots (or our testing team) didn’t experience any sort of hiccups during our initial test.

In any case, a 97% is truly an exceptional score for a robot on high pile carpets.

More Roborock Reviews

You can find our complete list of Roborock reviews here:

• Roborock S6 Review
• Roborock S5 Review
• Roborock S5 Max Review
• Roborock E35 Review (Xiaowa)
• Roborock E25 Review (Xiaowa Plus)
• Roborock S6 vs. S5 vs. S5 Max vs. S4 vs. E35 vs. E25

Usability & Maneuverability

The controls on top of the Roborock S4 are simple, which makes it intuitive and easy to use. 

Using the robot vacuum with the Roborock app is beneficial, providing feedback on cleaning cycles and reports. Downloading the app is worthwhile to get the best user experience.

The added customizable features in the app gives it more usability value.

As far as maneuverability, the round S4 robot vacuum moves around smoothly. It’s capable of reversing it’s position to prevent getting stuck on an obstacle. The S4’s low profile also means it can fit under most furniture.

• Weight: 7 pounds
• Width: 13.8″
• Height: 3.8″
• Turning: 360°

RELATED – Want to see how full sized vacuums compare? See our best vacuum cleaner reviews here.

Roborock S4 Maintenance

Maintaining the S4 doesn’t take much effort. Within the app you can monitor various maintenance tasks.

Here are the tasks involved:

1. Regularly empty the dust bin: This is the most common maintenance task. The dust bin should be emptied after each cleaning cycle.
2. Wash dust bin and HEPA filter: Allow proper drying time, a minimum of 24 hours before placing back in the vacuum.
3. Replace HEPA filters (as needed)
4. Replace battery (as needed): Most robot vacuum batteries last 2-3 years thought this is just an estimate as the manufacturer does not give a lifespan on the included battery.
5. Remove obstructions from brushroll: You’ll want to periodically remove the brushroll to remove hair and any other obstructions.

Is the Roborock S4 a good value?

With all the specs, features, and technology, is the Roborock S4 considered a good value?

It has a long run time, intuitive technology, and an accompanying app, which all add to the value. Unlike the S5 and S6 though, it only serves as a vacuum cleaner and doesn’t work as a mop.

While it lacks the mop, the price is notably better and the new drive-train system is a great upgrade. One of the most common issues for robot vacuums (especially budget robots) is they get stuck.

Being able to back up seems like a small thing, but it makes a big impact on keeping the Roborock S4 vacuuming without you needing to periodically rescue it.

When you combine this alongside the excellent cleaning performance it’s a solid value overall.

Roborock S4 Specifications

Should you buy the Roborock S4?

As far as robot vacuum cleaners go, the S4 model has some nice features and technology packed into it. 

Wondering if the Roborock S4 is the right vacuum cleaner for you?

The Roborock S4 is best if you want:

• Great cleaning performance: Cleaning performance was excellent overall. The S4 scored an average of 96% overall. Most notably was its ability to clean high pile carpets, where it scored a 97% (an area where robot vacuums tend to struggle). It’s every bit as good as any full sized vacuum cleaner (and better than many budget vacuums).
• Tech savvy options: The Roborock app creates a hands off approach to using the Roborock S4. Naming rooms, creating virtual barriers and “No-Go Zones,” getting cleaning reports, and being able to view cleaning cycle patterns are just a few of the options. For tech lovers, the S4 might be a good option.
• Long battery life:  The battery in the S4 model is a 5,200 mAH lithium ion powerhouse. It can last up to 150 minutes (2.5 hours) on one charge. Once the charge reaches a certain point, the S4 will head back to the charging station, recharge, and then get right back to where it left off.
• Intuitive navigation: The Roborock S4 offers several different ways to optimize its on-board navigation system. It uses a Z-shape cleaning pattern so it doesn’t miss a spot  and digitally maps and remembers rooms. The S4 also includes self-adjusting brush heads and suction to move from one floor type to the next with ease and without slowing down.

For more information on the Roborock S4 robot vacuum see here.

Updates

• December 1, 2020 – Roborock informed us that the S4 is being discontinued. We added an update alert to the top of the page.
• September 23, 2019 – Initial version of the page was published.