The ECOVACS window cleaning robot range splits into a high-rise line (WINBOT W3, W2S Plus) and a small-pane line (WINBOT mini 2). W3 suits vertical curtain walls and large panes; the mini 2 suits framed home windows and pitched skylights up to about 35°.
Buyers often assume the newest model is the general answer. It is not. The range is built around glass size and slope, and picking by model year rather than glass geometry is the most common buying error we see.
Where does the WINBOT W3 make sense?
Large panes, vertical faces, strong suction margin. W3-class machines typically hold around 2800–3000 Pa and handle panes above 2 m² comfortably. The wider pad covers more glass per pass, which matters when you bill by area.
It makes less sense on narrow domestic windows. A 600 mm sash is barely wider than the chassis, and the machine spends its cycle turning rather than cleaning.
Our full ECOVACS WINBOT W3 review goes through the edge behaviour on framed glass, which is the detail that decides whether it works on your building.
What does the W2S Plus add?
The W2S Plus version adds a more generous reservoir and a wider squeegee. On dusty exteriors it reduces repeat passes by roughly one in four in our testing notes. For a house with monthly cleaning, this is a marginal upgrade; for a maintenance crew, it pays.
Check the accessory rail before assuming the two models share pads. They do not. Buying the cheaper version and swapping parts later costs more than the difference.
When does the mini 2 win?
Small, framed, and often pitched. The mini 2 is designed for windows that a full-size unit cannot navigate. On skylights up to about 35° it holds well, provided the frame gives it a stop at the top edge.
The trade-off is area throughput. It is slower per square metre, and on large panes the extra passes eat the advantage. Read the ECOVACS WINBOT mini 2 review before choosing it for anything above 1.5 m².
| Model | Best glass | Slope limit | Pane size | Suction class |
|---|---|---|---|---|
| WINBOT W3 | Vertical curtain wall | ~10° | 2–6 m² | ~2800–3000 Pa |
| WINBOT W2S Plus | Vertical, dusty | ~10° | 2–6 m² | ~2800–3000 Pa |
| WINBOT mini 2 | Small framed panes | up to ~35° | 0.5–1.5 m² | ~2500 Pa |
What breaks first on ECOVACS units?
The pad edge. On framed glass the pad rubs the frame on every pass, and after 150–200 cycles the edge frays. A frayed pad loses suction locally and leaves a thin unwiped line down the glass.
The second failure is the safety line clip. It is a small plastic part and it cracks in cold weather. Replace it yearly; the cost is trivial compared to a dropped machine.
Who should not buy an ECOVACS unit?
Anyone with glass above 45° pitch, or with heavy mullion depth above 60 mm. The chassis cannot bridge deep reveals and it will stall against the frame.
Anyone expecting a maintenance-free appliance will be disappointed. These are tools with consumables: pads, filters, clips. Budget 40–70 euros a year for parts.
If your building mixes vertical glass with skylights, read the skylight robot review archive first — a single-model plan rarely covers both surfaces well, and the alternative machines in that archive approach slope differently.
One thing the spec sheets do not capture is noise. Measured at a metre, these machines run around 65 dB in normal mode and a little higher in max suction. That is fine outdoors and audible through a closed window indoors. Owners who plan to run a robot in a quiet office during meetings are usually surprised.
Also verify the app region. Some units ship locked to a regional server, which matters if you are buying across borders for a portfolio. Ask the seller which server your unit pairs with and whether firmware updates will reach it. That question has saved more than one buyer from a machine that could not be updated.
Frame geometry is worth measuring twice. A 20 mm internal frame lip helps the machine stop cleanly at the edge, but a 50 mm deep reveal traps the chassis and forces a manual reset on every pass. Walk the glass with a tape measure before you order, and note every rebate, handle and opening sash. That single walkthrough prevents more returns than any specification comparison.
Finally, consider the spare pad question before the first job. Pads degrade at different rates on different glass — coated surfaces polish them quickly, raw glass does not. Buy two spares at purchase. When one is drying after a wash, the other keeps the machine working, and you avoid the temptation to run a damp pad that will streak.
Service access is part of the purchase decision. Check whether your country has a repair centre or whether units go back to a regional hub. A two-week transit for a warranty repair means two weeks of manual cleaning, and for a commercial site that usually ends up cheaper to replace than to wait. Ask the local distributor for the average turnaround in writing; the number varies from five days to six weeks depending entirely on where you sit.
Key Takeaways
- Choose by glass geometry, not model year: W3 for big vertical panes, mini 2 for small framed and pitched glass.
- The W2S Plus reservoir and squeegee cut repeat passes by roughly a quarter on dusty sites.
- Pad edge fraying after 150–200 cycles is the top failure and the top cause of unwiped lines.
- Above 45° pitch or 60 mm mullion depth, no model in this range works.
- Budget 40–70 euros a year for consumables.