Rotating pads

Kärcher RCW 2 (window-cleaning robot with rotating pads): our review

Brand: KärcherOur methodology

Overall ratingiScores calculated by comparing verified specifications across our catalogue. No hands-on testing. Comparison of documented models, not an exhaustive market survey. n is the number of models compared for each criterion. No hands-on testing.
8.3/10
Documentation: partialNot confirmed by a verified source: Backup battery holding time.

Local offers are being verified.

Ecovacs WINBOT W2S OMNI, studio product shot Ecovacs WINBOT W2S OMNI 9.1/10 See our pick →
Scale from 6.5 to 9.6, the actual range of our scores. The dotted line shows the average across analysed models. Comparison of documented models, not an exhaustive market survey. n is the number of models compared for each criterion. No hands-on testing.
Suction pressure: 8.2/10: 3300 Pa, ahead of 50% of the models in the catalogue · n = 14. Average across analysed models: 8.1/10Water tank capacity: 8.7/10: 70 ml, ahead of 67% of the models in the catalogue · n = 18. Average across analysed models: 8.1/10Equipment: 8.1/10: 5 of 17 tracked features documented, ahead of 37% of the models in the catalogue · n = 27. Average across analysed models: 8.1/10Suction pressure8.2/10 · avg. 8.1Water tank capacity8.7/10 · avg. 8.1Equipment8.1/10 · avg. 8.1
The short version

For framed exterior windows, Kärcher RCW 2 offers automatic spraying

The RCW 2 pairs automatic spraying with rotating pads for framed exterior windows. We like its straightforward approach to regular upkeep. Our enthusiasm depends on how comfortably you can place, power, and retrieve it at each window.

Verdict

8.3/10

Regular exterior upkeep is the focus of our RCW 2 review

For the backyard view that keeps collecting weather residue, the RCW 2 earns our qualified recommendation. It is well placed overall in our scores, and its automatic spraying and rotating pads make sense for regular upkeep. Hand over the scrubbing, keep the responsibility.

Our verdict: We recommend considering it for accessible, framed exterior windows with mains power nearby. Ecovacs WINBOT W2S OMNI offers higher suction pressure, making that model the alternative we would consider when suction leads your decision.

Worth noting What holds us back is the modest suction specification. Avoid it if stronger suction is your leading priority when choosing a window cleaning robot.

Review by Romain Brunel, founder of Window-cleaning Robot Picks

Who it's for

Framed backyard windows give this robotic cleaner a clear role

  • Households maintaining framed exterior windows
  • Readers who prefer remote control
  • Regular upkeep with nearby supervision

This robotic cleaner suits someone whose framed exterior windows keep landing on the weekend chore list. A living room window overlooking the backyard is a sensible starting point if you can reach the exterior glass comfortably, arrange mains power, and stay nearby while the robot works. Its remote control and automatic spraying make sense when you want help with the repetitive scrubbing and can manage the transfers yourself.

Less suitable if

Skip this model if your project centers on frameless glass or you need cleaning away from an outlet. It is also a poor match for windows where placing and retrieving a robot would leave you stretching awkwardly. Easier access matters before any automated cleaning begins.

Dimensions

Plan each lift with a robot weighing 1,1 kg

Length29,2 cm
Width16 cm
Height7,1 cm
Weight without accessories1,1 kg
Tank capacity70 ml
Operating reachNot specified

Specifications

What the RCW 2 brings to spraying and scrubbing

Suction pressure3300 Pa
Water tank capacity70 ml
Robot height7,1 cm
Robot weight1,1 kg
Noise level62 dB
Power supply during cleaningMains-powered
Manufacturer's intended useHousehold
Indoor / outdoor cleaningOutdoor
Window compatibilityFramed
SprayingAutomatic
ControlRemote control
Safety featuresUPS backup battery
Scrubbing systemRotating pads
Cleaning modesQuick
Compatible glazingVertical framed glass
Backup suction durationNot specified

Pros

Automatic spraying takes liquid application off your chore list

  • Automatic spraying handles liquid application
  • Rotating pads provide the scrubbing action
  • Remote control for issuing cleaning commands
  • Quick cleaning mode for another cleaning option
  • UPS backup battery for attachment during power interruptions

Cons

RCW 2 asks you to weigh suction, outlet access, and framed glass

  • Suction pressure sits among the category's lowest advertised levels
  • Requires mains power throughout cleaning
  • Verified compatibility is limited to framed windows
  • You still move it between windows and supervise

Our scores explained

How the RCW 2's specified equipment shapes our assessment

Every model on the site is scored on the same criteria, using the same scale: its position among models with verified data for that specification. Last place earns 6.5, first place 9.6, and the rest are scored in proportion to their rank. Here is how this model's scores are calculated.

Two model counts: the rank and average include product pages on this site scored for the criterion; the calculation compares the model with all catalogue models whose specification is verified, with or without a product page. A score assigned at publication may remain without a verified specification, so the first count can sometimes be higher.

Suction pressure: 8.2/10

Kärcher RCW 2 scores 8.2/10 on this criterion. Across the 14 product pages on the site with a score for this criterion, the average is 8.1: above average, Rank 7 out of 14.

View calculation
Shared baseline: last place in the ranking6.5
Suction pressure: 3 300 Pa ; 7 perform worse, 6 perform better, 1 are tied (including this model), among the 14 catalogue models with this specification verified+1.7
Suction pressure score8.2/10

Calculation: (7 + 1 ÷ 2) ÷ 14 = 53.57% of the ranking; 6.5 + 53.57% × 3.1 = 8.2/10, rounded to one decimal place.

Water tank capacity: 8.7/10

Kärcher RCW 2 scores 8.7/10 on this criterion. Across the 18 product pages on the site with a score for this criterion, the average is 8.1: above average, Rank 5 out of 18.

View calculation
Shared baseline: last place in the ranking6.5
Water tank capacity: 70 ml ; 12 perform worse, 4 perform better, 2 are tied (including this model), among the 18 catalogue models with this specification verified+2.2
Water tank capacity score8.7/10

Calculation: (12 + 2 ÷ 2) ÷ 18 = 72.22% of the ranking; 6.5 + 72.22% × 3.1 = 8.7/10, rounded to one decimal place.

Equipment: 8.1/10

Kärcher RCW 2 scores 8.1/10 on this criterion. Across the 27 product pages on the site with a score for this criterion, the average is 8.1: average, Rank 11 out of 27.

View calculation
Shared baseline: last place in the ranking6.5
5 features found out of 17 tracked: 10 perform worse, 10 perform better, 7 are tied (including this model), among the 27 catalogue models with this specification verified+1.6
Equipment score8.1/10

Calculation: (10 + 7 ÷ 2) ÷ 27 = 50% of the ranking; 6.5 + 50% × 3.1 = 8.1/10, rounded to one decimal place.

Recorded features: Indoor / outdoor cleaning (Outdoor), Spraying (Automatic), Control (Remote control), Safety features (UPS backup battery), Cleaning modes (Quick).

The retailer does not specify: Compatible surfaces. These features are not counted.

The retailer does not specify “Backup battery holding time”: this criterion earns no points and is excluded from the overall score.

Overall score: 8.3/10, the average of the 3 scores above.

Our full methodology

Detailed analysis

The exterior of your living room picture window can turn a pleasant Saturday into a ladder negotiation. The Kärcher RCW 2 offers automatic spraying, rotating pads, and remote control for household use on framed outdoor windows. We see an appealing way to hand over part of that chore, with some clear boundaries. You still arrange the power connection, supervise the work, and move the robot between windows.

The RCW 2 window cleaning robot advertises 3300 Pa of suction

The living room picture window can look reasonably clean until the afternoon sun turns every smudge into a small announcement. For that familiar chore, the RCW 2 offers a household robot intended for outdoor cleaning on framed windows. We would consider it for accessible exterior glass where you can handle placement and retrieval comfortably. The pads take over the repetitive scrubbing; getting the robot onto each window remains your job. Is that the part of window cleaning you most want to hand over?

Its advertised suction pressure is 3300 Pa, among the lowest advertised suction levels for window cleaning robots. That is our main reservation: we would favor stronger suction when choosing between otherwise appealing options. The figure does not tell you how effectively the rotating pads will remove fingerprints or weather residue, and it certainly is not a promise against falling.

Frame compatibility matters just as much as the motor specification. Choose this model around the windows it supports, rather than assuming every glass surface around the house belongs on its route.

A 70 ml tank puts refills on the RCW 2's chore list

A spring Saturday devoted to the windows usually starts with enthusiasm and ends with a damp sleeve. Automatic spraying and rotating pads give this robot a practical role: applying liquid and scrubbing the glass while you supervise. Your sleeve may finally get the afternoon off.

The 70 ml reservoir is a typical tank size for this category. Think of it as a refillable supply for working across your windows, rather than a promise to finish the entire exterior without returning to the sink. Dirt and spraying needs affect how far each fill goes. We like the straightforward combination of automatic spraying and rotating pads for regular upkeep.

A quick cleaning mode is also specified. Its name makes it appealing when you want to tackle routine marks, but it does not establish a cleaning time or promise to remove stubborn buildup. Cloth condition and cleaning solution still matter, particularly at the window corner where the setting sun reveals every lingering mark.

At 62 dB, this window cleaning robot belongs in an active afternoon

The advertised noise level of 62 dB sits around the category average. That gives you a sensible planning reference: treat cleaning as an audible household activity, rather than counting on a quiet background companion. A patio coffee while you stay nearby is a more fitting scene than expecting the robot to disappear into the soundscape.

You still do the lifting. Its 1,1 kg weight is the load you will handle when placing it on the glass, retrieving it, and moving to the next window. Check that the window position lets you manage that comfortably; an awkward reach does not become convenient simply because the pads move themselves.

The 7,1 cm height describes how far the body projects from the glass. Use that dimension when considering nearby obstructions, without assuming it establishes clearance around every frame. Access remains part of the job, especially on an upstairs exterior window that already makes you reach for a stepladder. Remote control cannot solve an uncomfortable placement.

Keep an outlet nearby for the RCW 2 window cleaning robot

Before placing the Kärcher RCW 2 on an exterior window, work out where its power connection will run. Cleaning requires mains power. The remote control gives you a way to issue commands, but it does not remove the need to prepare the window, arrange the connection, or move the robot afterward.

The UPS backup battery is intended to keep the robot attached during a power outage, giving you an opportunity to retrieve it. It does not enable unplugged cleaning or guarantee against a fall. Manufacturers' manuals instruct users to secure a safety tether to a fixed anchor point and stay nearby, especially for upstairs exterior work. They also advise against cleaning exterior windows in the rain.

The supplied accessories are not confirmed: ask the retailer about the safety tether, extension cord, and replacement pads, along with the warranty, return policy, and customer support. Having those answers before ordering makes it easier to prepare the connection and keep usable pads available.

For broad picture windows, compare the RCW 2's 70 ml tank

Would fewer refill interruptions make a long stretch of glass less of a chore? Lubluelu CHYW201 for larger windows is better suited to large picture windows thanks to a larger tank, with a water tank capacity of 160 ml. That extra liquid gives you more room to work between refills, although dirt and spraying needs still determine coverage. Lubluelu CHYW201 also has higher suction pressure at 6500 Pa. Lubluelu CHYW201 is better rated overall.

Ecovacs WINBOT W2S OMNI addresses our main reservation with higher suction pressure at 8000 Pa. Ecovacs WINBOT W2S OMNI also holds more liquid, with a tank of 80 ml, giving you a little more supply before a refill. Ecovacs WINBOT W2S OMNI is better rated overall.

The RCW 2 is well placed overall in our scores. Its remote control, automatic spraying, and rotating pads form a straightforward package for framed exterior windows. For accessible glass and regular upkeep, that combination makes sense. For large expanses, give reservoir capacity real weight in your decision: every refill is another interruption to the afternoon.

Romain Brunel

Analysis by Romain Brunel

Founder of Window-cleaning Robot Picks

We analyse window-cleaning robot manuals, technical specifications and buyer reviews. We explain surface, power supply and safety requirements, highlighting missing information and the limitations of the available data.

Updated on October 4, 2026

Frequently asked questions

Your questions about the RCW 2 before ordering

Can the RCW 2 clean without being plugged in?

No. The RCW 2 requires mains power during cleaning. Its UPS backup battery is intended to keep it attached during a power outage, not to continue cleaning unplugged. A fall remains possible. Stay nearby and keep the safety tether secured as manufacturers' manuals instruct.

Is the RCW 2 suitable for frameless windows?

The verified window compatibility is framed glass, and its specified use is outdoor household cleaning. Choose it for that combination. Frameless windows fall outside the supported information, so this model would not be our recommendation for that job.

Does automatic spraying mean I can forget about pad maintenance?

No. Automatic spraying supplies liquid, while rotating pads provide the scrubbing action. Cleaning results still depend on the dirt, solution, and cloth condition. Make pad care part of your upkeep instead of expecting spraying alone to handle every mark.

What should I check before ordering for upstairs windows?

Check whether you can place and retrieve the robot comfortably and arrange mains power. Confirm the supplied tether and extension cord with the retailer. Manufacturers' manuals instruct users to attach the tether to a fixed anchor point and remain nearby, especially for upstairs exterior cleaning.

At a glance

Kärcher RCW 2

8.3/10Overall rating

Pros

  • Automatic spraying handles liquid application
  • Rotating pads provide the scrubbing action
  • Remote control for issuing cleaning commands
  • Quick cleaning mode for another cleaning option

What to know before buying

  • Suction pressure sits among the category's lowest advertised levels
  • Requires mains power throughout cleaning
  • Verified compatibility is limited to framed windows
  • You still move it between windows and supervise
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