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Roborock S4 Max review: an efficient robot vacuum with a great app and really good suction

Written by Eileen Brown, Contributor
Roborock S4 Max review sweeping robot vacuum with really good power zdnet

Roborock S4 Max

8.4 / 5

pros and cons

  • Easy to connect to app
  • 180 minute cleaning time
  • Auto-adjusts power when on carpet
  • No auto-empty station

I have tested a lot of multi-function robot vacuums recently – robots that sweep and mop simultaneously like the quirky D-shaped Hobot Legee 688, the powerful 360 S9, or the Ecovacs T8 robot and accessories. It is not often I get to take a look at a single function sweeping robot.

The Roborock S4 Max robot vacuum, released on 9th October combines all the features I really like about the Roborock range (LIDAR navigation, multi-level mapping, no-go zones, and simplified app connection).

The S4 Max has a good 2000Pa motor that will automatically adjust its suction power on hard floors and increase its suction to maximum when it encounters carpets and rugs.

It will remember up to four different maps in your space to recognise multi-level areas, or you can configure the robot to clean a specific area at a specific time of day.

The S4 Max will recognise any no-go zone and not cross it. I have a super high threshold in my house that stumps almost every robot vacuum I review. I find it is better to set an no-go zone so I do not need to rescue the robot any time it is sweeping.

The app, which, unlike some other robot vacuum apps, easily connects to my mobile device, lets you name each room and configure what time you would like specific rooms to be cleaned.

The mess around the dog bowl can be cleaned after each meal, specific zones can be set around items such as the dog water dish which ensures that it will not get knocked around during cleaning.

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The S4 Max has a 5,200mAh battery which will clean for up to three hours – longer than the 360 S5 single-use robot, or the Onson J10C. Roborock says that this will clean up to 300 square meters.

This cleaning range would clean the entire ground floor of my house more than three times before going back to its charging dock.

If the battery level gets low, the S4 Max will return to the charging station to recharge its battery, return to its last place of cleaning, and finish off sweeping the area.

Like most robot vacuums it has an anti-drop sensor which will stop the robot tumbling down stairs. It also seems to get stuck under furniture less often than previous versions I have tried.

It has a reasonably large 460ml dustbin, and a brush cleaner usefully stowed under the S4 Max's lid – so you do not lose the cleaning tool.

The only thing that is missing from the Roborock product range, is the auto-empty docking station. 

I have come to love these time-saving auto-empty stations since I looked at the Neabot in June 2020, and Ecovacs Deebot T8 in September. Who knows – a similar offering might be in the pipeline for future models?

All in all, the Roborock S4 Max is a really powerful single-function robot that is perfect for large swathes of carpet, or mixed flooring areas. 

At under $430, it will cope with all the floor surfaces you place it on – and sweep them really well. It is well worth the investment