Roborock S4 Robot Vacuum Cleaner

Roborock S4 Robot Vacuum is mid-range robot vacuum cleaner featuring smart LDS navigation, and is optimized for vacuuming large areas of bare floors and low-pile carpeting.

Roborock S4 Robot Vacuum is WiFi enabled unit, fully controlled by Mi Home app. Unit lacks classic IR controller, but using Mi Home app, user can set all required settings, receive reports, statuses etc.

Published: November 27, 2019.

roborock s4 1

Roborock S4 Robot Vacuum Features and Specifications

Roborock S4 physical dimensions are 3.78 inches (9.6 cm) in height, 13.78 inches (35 cm) diameter, and it weighs 7.72 lbs (3.5 kg).

Roborock S4 is slightly taller than other similar units because of the LDS sensor positioned on top of the unit. Nonetheless, it is able to clean under most beds, sofas and similar objects.

Unit is powered by 14.4 volts 5200 mAh lithium battery, providing energy for up to 150 minutes of continues operation.

When the battery is discharged, it takes ~240 minutes (~4 hours) to fully charge it again.

Thanks to the advanced LDS navigation system that ensures features like mapping, Roborock S4 support the 'Recharge and Resume' feature - when robot detects 'low battery' condition, it stops with the cleaning, recharge itself to 80% to save time (so-called 'Top-Up Charging') and then continues with the cleaning from the spot where 'low battery' condition was detected.

Because of this and other features, Roborock S4 is suitable for medium to large homes and apartments (>200 m2).

Charging dock should be placed against the wall, with some free zone around it to help the unit locate the charging dock.

Note: Roborock S4 is simple to use and maintain robot vacuum cleaner, especially for the people used to control the appliances with smart phones. When the unit arrives, be sure to read the manual thoroughly.

roborock s4 features

Other features supported thanks to the Smart LDS Navigation system include Apartment Layout, Running Route, Map Saving, and Selective Cleaning.

All these features are available via Mi Home app. Also, Roborock S4 support the use of Amazon Alexa, but at the moment, it does NOT support the Google Home Assistant - since other Roborock robot vacuums support the use of Google Home Assistant, its use will probably be available soon (via firmware update, for example).

Main Mi Home app functions include Live map, Cleanup records, Robot location, Change cleaning mode, Remote control mode, Control other Mi Home devices, View cleaning history, View robot status, Change voice pack, and Firmware updates.

Note: because of the updates to the firmware and Mi Home app itself, list of available functions may change over time.

Smart LDS Navigation System accuracy is ~2 cm (~0.8 inches) and is combined with other set of sensors that help with the navigation and protect the unit and walls/objects.

Thanks to the cliff sensors, unit will not fall down the stairs, however, it also may have issues with really dark carpets and tiles.

Note: although it is not officially supported, some users place dark dull tape on the floor - when the unit arrives, it detects the cliff (false-positive) and return back. Since this is not 100% foolproof and since virtual walls/no go zones may be added through the smart home app, this is not recommended.

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Roborock S4 robot vacuums cleaning mechanisms include single side brush used for sweeping edges and corners, floating brushroll that adjust itself automatically to the vacuumed floor type and rather strong, 2000 Pa suction.

Since Roborock S4 is intended for vacuuming bare floors and low-pile carpeting, it doesn't come with 'Carpet Recognition' and 'Carpet Boost' features, found on many other Roborock vacuums.

But, side brush, main brushroll and strong suction do excellent work on various bare floors and low-pile carpets, thoroughly cleaning various types of dry dirt, including dust, dry pet food, pet and human hair etc.

roborock s4 main brush

Also, Roborock S4 is able to climb 'only' 0.59 inches (15 mm) in height obstacles, while other Roborock units are able to climb onto 0.79 inches (20 mm) obstacles.

Roborock S4 also lacks mopping feature (found on Roborock Xiaowa E2/E20/E25, Roborock Xiaowa E3/E30/E35, Roborock S5, Roborock S6), but it comes with 640 ml dirt cup (for example, S5 and S6 - 480 ml).

Air filtration is based on the pleated E11 HEPA air filter - filter is washable, keeping the maintenance costs low.

Roborock S4 Cleaning Modes

Roborock S4 come with several cleaning modes that are available via Mi Home App.

Pin-n-Go is not actual cleaning mode. Using the Mi Home App, user can send the unit to the certain point on the map - although not officially supported, but excellent way for distributing drinks and other smaller packages across the home :)

Zone Cleanup - using Mi Home App, user can draw a zone on the map and send the robot to clean that specific area.

Virtual Wall/Barrier is used for preventing the robot entering certain room - just draw a line where the door is and robot will not cross it.

Virtual No-Go Zone is used for preventing the robot entering certain area in the cleaned room.

Do Not Disturb (DND) Mode - in this mode, unit will not start the cleaning task, there is no voice alerts and the power light is dimmed. By default, DND mode is set from 10:00 PM to 08:00 AM and can be modified (or disabled) using Mi Home App.

Cleaning Mode Strength may be changed using Mi Home App - available modes include Quiet, Balanced, Strong and MAX mode. The Balance mode is default suction strength mode, offering long operating time and good suction. Extra piles of dirt should be vacuum using Strong or even MAX suction modes, although these modes discharge the battery rather fast.

Roborock S4 Maintenance

Roborock S4 maintenance is very simple to the maintenance procedures of other similar robot vacuums and include:

- dirt cup: dirt cup should be emptied after each (larger) cleaning task. If the daily schedule job is set, consider emptying the dirt cup on a daily basis.

- main brushroll should be cleaned weekly,

roborock s4 filters- main air filter and dirt cup should be washed on a bi-weekly basis. Note: always let the air filter air dry for at least 24 hours.

- charging dock should be wiped using dry cloth monthly.

- side brush should be cleaned every month, too. Also, replace it after 3-6 months or when being visibly worn out.

- wheels, and especially omnidirectional wheel should be cleaned monthly or when needed.

- sensors and rest of the robot's body should be wiped using soft, dry cloth monthly.

Again, when the unit arrives, be sure to read the manual, charge the unit and install Mi Home App.

Roborock S4 vs S5 vs S6

Roborock manufactures several similar robot vacuum cleaners, sharing similar design and features.

The following chart lists several Roborock robot vacuums, including Roborock S4, S5 and S6, with their most important features and specifications:

Model Roborock Xiaowa Lite C10 (C1)
Roborock Xiaowa E20 (E2*) Roborock Xiaowa E30 (E3*) Roborock S4 Roborock S5 (S5*) Roborock S6
Photo table roborock c10 table roborock e25 table roborock e35 roborock s4 table table roborock s5 roborock s6 table
Navigation Adaptive Navigation (Random) Inertial Navigation Inertial Navigation Smart LDS Navigation  Smart LDS Navigation Smart LDS Navigation 
Map (No Mapping Feature) Apartment Layout Apartment Layout  Apartment Layout, Running Route, Map Saving, Selective Cleaning  Apartment Layout, Running Route, Map Saving Apartment Layout, Running Route, Map Saving, Selective Cleaning 
Maximum Suction 1600 Pa 1800 Pa 2000 Pa 2000 Pa  2000 Pa 2000 Pa 
Suitable Area 80-120 m2 120-150 m2 150-200 m2 >200 m2  >200 m2 >200 m2 
Operating Time 80 minutes 100 minutes 150 minutes 150 minutes  150 minutes 150 minutes 
Charging Time 240 min 240 min  240 min  240 minutes  240 minutes 240 minutes 
Battery Capacity 2600 mAh  2600 mAh 5200 mAh 5200 mAh  5200 mAh 5200 mAh 
Dynamic Brush Yes Yes Yes Yes  Yes Yes 
Weight 6.61 lbs (3 kg) 6.61 lbs (3 kg)  6.61 lbs (3 kg)  7.72 lbs (3.5 kg)  7.72 lbs (3.5 kg) 7.72 lbs (3.5 kg) 
Robot Height  3.54 inches
(9 cm)
3.54 inches
(9 cm) 
3.54 inches
(9 cm) 
3.78 inches
(9.6 cm) 
3.78 inches
(9.6 cm)
3.78 inches
(9.6 cm) 
Robot Diameter  13.78 inches (35 cm) 13.78 inches (35 cm)  13.78 inches (35 cm)  13.78 inches (35 cm)  13.78 inches (35 cm)  13.78 inches (35 cm)
Rated Power 50 watts 54 watts 57 watts 58 watts  58 watts 58 watts 
Sweeping and Mopping Sweeping Only
Yes Yes Sweeping Only Yes Yes 
Carpet Recognition Yes Yes Yes No Yes Yes 
Carpet Boost Yes Yes Yes No Yes Yes 
Automatic Recharge and Resume Recharge Only Yes Yes Yes  Yes Yes 
Zone Cleaning, No-Go Zones, High Precision Map No No No Yes  Yes Yes 
Scheduling Yes Yes Yes Yes  Yes Yes 
Dirt Cup 640 ml 640 ml 640 ml 640 ml 480 ml 480 ml 
Water Tank - 150 ml 150 ml - 150 ml 160 ml
Floor Types Bare Floors, Low- and Medium Pile Carpets Bare Floors, Low- and Medium Pile Carpets Bare Floors, Low- and Medium Pile Carpets Bare Floors, Low  Pile Carpets Bare Floors, Low- and Medium Pile Carpets Bare Floors, Low- and Medium Pile Carpets
Climbing Height 0.79 inches (20 mm) 0.79 inches (20 mm)  0.79 inches (20 mm)  0.59 inches (15 mm) 0.79 inches (20 mm)  0.79 inches (20 mm) 
Balance Mode Noise 55 dB 55 dB  55 dB  59 dB 62 dB 58 dB
HEPA Filter E11 (Washable) E11 (Washable) E11 (Washable) E11 (Washable)  E11 (Washable) E11 (Washable) 
iPhone & Android App Mi Home Mi Home  Mi Home  Mi Home  Mi Home  Mi Home 
Amazon Alexa, Google Home Support Yes Yes Yes Alexa Only Yes Yes 
Obstacle & Cliff Sensors Yes Yes Yes Yes  Yes Yes 
 Warranty 12 months 12 months 12 months  12 months  12 months  12 months
Amazon Link - Roborock E25 Roborock E35 Roborock S4 Roborock S5 Roborock S6

Roborock S4, S5 and S6 feature advanced navigation system, with S6 having the most advanced one and the S5 the least advanced one - S5 doesn't feature Selective Cleaning, while both S4 and S6 come with that feature (S4 and S6 are newer models than S5).

Also, Roborock S4 lacks mopping function, while S5 and S6 feature smaller dirt cup (S4 640 ml vs 480 ml on S5 and S6), they also feature removable water tank - mopping function is optional.

All three robots are of the same size and weight, they are being powered by the same battery, and have the same maximum suction.

But, Roborock S4 doesn't feature Carpet Recognition and Carpet Boost - it is optimized for bare floors and low-pile carpets.

All three units feature 12 months warranty period.

Note: some sites claim that Roborock S6 comes with 24 months warranty, but according to the Roborock official website, they ALL feature 12 months warranty.

Prices of these vacuums differ according to the features they have:

So, be sure to choose according to your own needs and preferences.

For more reviews and recommendations, check Roborock S4 Robot Vacuum Amazon link (link opens in the new window).