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Roborock S4 Max Review

The Roborock S4 Max is the newest version of the S4 to come off the production lines. This robot vacuum offers max suction, advanced mapping, and excellent cleaning performance. But is it worth the cost?

Let’s find out!

Self-Adjusting Suction for Better Performance

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Roborock S4 Max

The Roborock S4 Max robot vacuum is an upgraded version of the standard S4. It offers advanced digital mapping, improved navigation, 150 minute run time, no-go lines, and great cleaning performance (94% overall in our tests). Performance on low pile carpet struggled a bit, only 87%, but it jumped back up to 96% for high pile carpet performance. It’s one of the best performing Roborock’s we’ve tested on high-pile carpet.Check Price

Pros

  • A multi-level mapping system can automatically recognize different floor plans
  • Removed 99% of debris by weight in our cleaning tests.
  • 150 minute run time
  • Excellent navigation
  • Can clean rooms by specific names

Cons

  • Pricier than the preceding S4 model
  • No mopping attachment (but less expensive, as a result)

Table of Contents

Roborock S4 Max Design

The design of the S4 Max is a sleeker and simpler version of the S4. It has a matte black aesthetic with black controls.

Roborock S4 Max design - top

The laser navigation system is located more towards the middle of the vacuum, a shift from the S4 which located it towards the front of the vacuum.

Roborock S4 Max

Above the navigation system, there are two simple buttons:

  • 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)

Additional controls from the Roborock are accessible using the Roborock app, where you can schedule cleanings, view digital map reports, and even see maintenance or error reports.

What’s on the bottom of the vacuum?

The underside of the S4 Max looks similar to the S4, but with a few upgrades.

Roborock S4 Max Brushroll
Roborock S4 Max Brushroll

It has the same spiral brushroll with a hybrid design of rubberized paddles and spiral bristles. The floating brushroll adapts its height to match the current flooring type that it’s cleaning to help with overall performance.

There are three wheels, two larger wheels on each side of the brushroll and one smaller wheel at the front of the vacuum for steering and 360° turns.

Wheels on the S4 Max
Wheels on the S4 Max are designed for greater climbability and obstacle maneuverability

As an upgrade over the S4, the Max has a higher obstacle clearance ability, making it easier to get on and off carpets and rugs.

There is a single spinning 5-arm brush on one side of the vacuum to sweep debris from edges and corners.

The S4 Max accelerates when cleaning along corners and slows down when out in the open to reduce debris being flung around the room.

Lastly, the S4 Max has a series of edge sensors along the edges for drop detection and larger charging contact pins for more effective charging at the base station.

Underside of the S4 Max robot vacuum
Underside of the S4 Max robot vacuum

The exact position of all of these elements slightly changes between the S4 and Max.

Here’s what’s new on the S4 Max:

  • Brushroll moved a little towards the back by a couple of inches
  • Space between 5-arm spinning brush and brushroll grew just slightly
  • Charging contact pins on the S4 Max, not visible on the standard S4

Cleaning Performance

For the cleaning performance tests we run each vacuum through a assessment of cleaning performance.

S4 Max Cleaning

We test on three different floor types, including:

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

And on those floors, we spread a mix of debris, including:

  • 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.

Roborock S4 Max cleaning carpet
Roborock S4 Max cleaning carpet

We use the same vacuum cleaning process to test all our vacuum cleaners (see our full list of robot vacuum reviews). 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 the best robot vacuums here.

Testing Data

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

Overall

95.7%

Hardwood

99%

Low Carpet

91.5%

High Carpet

96.5%

Hardwood Floor Cleaning

The performance cleaning hardwoods was fantastic and the S4 Max was able to clean up to 99% of the debris tested on hardwood floors.

Cleaning performance of the S4 Max on hardwoods
Cleaning performance of the S4 Max on hardwoods

It left a miniscule amount of visible sugar, but not enough to trigger any measurement on our digital scale.

Low-Pile Carpet Cleaning

For low pile carpet cleaning, the S4 Max captured 91.5% of debris. This was less than I expected honestly, especially because the S4 captured 93% of debris tested.

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

Cleaning performance of the S4 Max on low pile carpet
Cleaning performance of the S4 Max on low pile carpet

It’s unclear exactly why the S4 Max was only able to remove 91.5%. Much like the original S4, it may not be able to create as much of a suction seal due to the relatively lower floor height of low pile carpet.

Whereas on high pile carpets, this is less of an issue, because the high pile fibers are literally closer to the brushroll. This would create a better seal with the carpet, and therefor greater suction.

In any case, 91.5% isn’t a bad carpet cleaning removal rate. But we had hoped for more.

High-Pile Carpet Cleaning

For high carpet tests, as mentioned above, the S4 Max kicked into Max mode and was able to clean up to 96.5% of the debris tested.

Cleaning performance of the S4 Max on high pile carpet
Cleaning performance of the S4 Max on high pile carpet

The remaining debris mainly included fine sugar and kitty litter particles deeper in the carpet fiber, but overall the S4 Max did a great job.

The performance on high pile carpet feels as high quality as any Roborock we’ve tested to date.

More Roborock Reviews

You can find our complete list of Roborock reviews here:

Cleaning Modes

There are four main cleaning modes on the Roborock S4 Max.

Roborock S4 Max cleaning modes
Roborock S4 Max cleaning modes

Modes include:

  1. Quiet: Operates with less suction power so it makes less noise. Also the least section power of the 4 cleaning modes.
  2. Balance: Standard suction power. A good balance between power, performance, and run time.
  3. Turbo: Vacuums at a higher speed, allowing the cleaning job to finish more quickly.
  4. Max: Creates the maximum level of suction and seal possible. Ideal for carpets and high traffic areas.

How does it clean?

The S4 Max cleans around the edges first and then cleans the rest of the room in a straight pattern. You can check out the cleaning map from the Roborock S4 below.

Roborock app cleaning map
Roborock app cleaning maps

Size & Dimensions

The Roborock S4 Max is the same size as the S4. The exact dimensions are listed below.

  • Diameter: 13.8″
  • Height: 3.5″
  • Weight: 8 pounds
Size of the Roborock S4 max robot vacuum
Size of the Roborock S4 max robot vacuum

Accessories & Parts

The list of accessories included with the S4 Max is a simple set of tools, much like the accessories that come with the standard S4.

HEPA filter with dust bin for the Roborock S4 Max
HEPA filter with dust bin for the Roborock S4 Max

What’s in the box?

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

  • 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. One HEPA filter is installed and one replacement is included.
  • User manual: information on use, care, and troubleshooting the Roborock S4 Max is included in the user manual
Charging station for the Roborock S4 Max

Roborock S4 Max Features

The features on the Roborock S4 Max includes everything that the S4 has and a few more bells and whistles.

Here’s exactly what you’re going to get.

Profile view of the Roborock S4 Max
Profile view of the Roborock S4 Max

App Control

The S4 Max offers wifi-connectivity and can be controlled with a smartphone using the Roborock app.

In the app, you can:

  • 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 Max has similar navigation as the standard S4, but with a few notable upgrades.

Roborock S4 Max digital map
Roborock S4 Max digital map

The on-board laser scans the room at 300 revolutions / minute and then uses that information to map out each room’s dimensions to +/- 2 cm.

After it has effectively mapped an area, the S4 Max can automatically recognize different levels of a home or recognize individual rooms automatically.

This helps the S4 Max to be more efficient at cleaning as well as finding its way back to the base after the cycle is complete.

At any point during or after a cleaning cycle, you can view the app to see the progress and if the robot missed any spots. Trouble areas can easily be identified and addressed.

Recharge & Resume

This feature is not unlike the same feature offered by Roomba robot vacuums.

During a cleaning cycle, if the battery begins to run low, it will return to the charging base, juice up, and then return to the spot where it left off to complete the cleaning.

Roborock S4 Max robot vacuum

With this feature, the Robrock has an extended run time and will basically keep cleaning until the job is finished.

No-Go Zones

Similar to other advanced Roborock models, the S4 Max has the ability to mark off specific areas as “no go zones” and prevent the vacuum from entering those spaces.

Roborock app no go zones
You can create no go zones and virtual lines to block the robot from entering certain areas

Areas can be marked off using a straight line or by drawing a box around an entire space, as shown above.

You can also limit where the S4 Max goes by naming specific rooms in the app and programming the vacuum to skip those titled rooms.

Usability & Maneuverability

Let’s talk usability.

The Roborock S4 Max is user-friendly and has a design that enables minimal user interaction. Just plug it in and let it get to work.

You can set up customized cleaning cycles completely from the app, like:

  • Naming rooms or separate zones
  • Setting up No-Go lines
  • Viewing digital map
  • Schedule a cleaning in the future
  • See remaining battery life or run time
  • View maintenance reports

Regarding maneuverability, the S4 Max is great at making tighter turns, straighter cleaning paths, and longer cleaning cycles.

Top open on the Roborock S4 Max
Top open on the Roborock S4 Max

It has a low-profile body that can relatively easily squeeze under furniture as well as improved climbability for better navigating flooring transitions and flooring of different heights.

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

Roborock S4 Max Maintenance

Maintenance on the Roborock S4 Max is straightforward and requires the same tasks you’d need to do on any most any other robot vacuum.

All of the maintenance tasks are listed in the app, making it easy to see the current status and know when it’s time to clean or replace.

Monitoring maintenance tasks within the app
Parts monitor within the Roborock app

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 2-4 years. That said, this is just an estimate as Roborock 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.
Installing the dust bin on the Roborock S4 Max

Is the Roborock S4 Max a good value?

Considering all of the specs, features, and cleaning performance, how does the S4 Max compare? And are the upgrades worth the added cost?

Here’s the breakdown.

Overall, the S4 Max is a quality robot vacuum, if you’re looking for a great robot vacuum and don’t need mopping capability.

Spinning side brush on the Roborock S4 Max robot vacuum
Spinning side brush on the Roborock S4 Max

It excels at:

  • Digital mapping
  • Hardwood cleaning performance
  • High pile carpet cleaning performance (auto carpet boost)
  • Extended run time
  • In-app options
  • Obstacle climbability

It struggles a bit with:

  • Low pile carpet cleaning performance

All in all, I would say the S4 Max is a great value and has some nice advanced features over the more basic S4.

Roborock S4 Max Specifications

SpecificationsRoborock S4 Max
TypeRobot
ManufacturerRoborock
ModelS4 Max
Width13.8"
Height3.5"
Weight8.0 lbs.
Floor TypeAll (indoor)
Suction Power2,000 Pa
Battery5,200 mAh
Run Time150 mins
Cleaning Area~2,700 sq. ft.
Dust Bin Capacity480 mL
Includes Digital WallYes
ReturnsVaries by retailer, other retailers will vary
Warranty1-Year Limited
PriceCheck Price

Should you buy the Roborock S4?

The Roborock S4 Max is a notable step up from the standard S4 in most cases.

I would recommend the S4 Max if you’re looking for the following in a robot vacuum:

  • Solid Cleaning Performance: While the S4 Max wasn’t the absolute best we’ve seen in terms of cleaning performance, it’s more than sufficient for the vast majority of homes. Moreover, at this price point it still offers excellent cleaning performance for the money, making it a solid value.
  • Advanced navigation: The digital mapping capability of this vacuum is fantastic. It can effectively map an entire home, including multiple levels. Once the maps are generated, the S4 Max can auto-detect the level it’s on and even the room it’s cleaning. You can set up different zones for cleaning or mark off spaces entirely. It’s as user-friendly as most any high-end Roborock vacuum.
  • Long battery life:  The runtime of the S4 Max us up to 150 minutes and then even longer with the Recharge and Resume feature. This allows the vacuum to return to the base, charge up, and resume cleaning where it left off.
  • Auto-detect flooring: As the S4 Max engages with different floor types, it will automatically change suction power and brushroll height. This feature is something unique to the S4 Max and provides a deeper clean for carpet. The one exception would be low pile carpet where the auto-suction struggled a bit and it didn’t seem to recognize that it was on carpet.

For more information or to check the price for the Roborock S4 Max, click here.

Excellent Navigator & High Pile Carpet Performance
  • 97%
    Design - 97%
  • 95%
    Performance - 95%
  • 94%
    Quality - 94%
  • 97%
    Usability - 97%
  • 95%
    Value - 95%
96%

Summary

The Roborock S4 Max is the updated version of the Roborock S4 robot vacuum. It has great cleaning performance and advanced navigation options. Digital mapping allows for the S4 Max to auto-detect different levels of a home, specific rooms, and changing floor heights. Overall cleaning performance was 93%, with nearly flawless results on hardwoods. You can set up No-Go zones where you want the vacuum to skip or schedule cleanings around specific areas. If you’re looking for a robot vacuum (and don’t need the mopping feature), the S4 Max is a great option.

About Derek Hales

Derek HalesDerek Hales is the Founder and Editor-in-Chief of ModernCastle.com. He has been featured in Fast Company, Reader's Digest, Business Insider, Realtor.com, She Knows, and other major publications. Derek has a Bachelor's Degree in Business Administration from Kansas State University. Hales has been testing and reviewing products for the home since 2014.

Need Help? Ask Your Question Below

  1. Thanks for doing a review on the new model so quickly. Is the S4max essentially identical to the S5max (power, wheel placement, brush type) without the mop system?

    Reply
    • In looking at the side-by-side spec comparison table from Roborock, yes. The S4 Max and S5 Max appear to be identical in terms of specs and hardware. With the only difference being the mopping attachment on the S5 Max.

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