Pick the Lingkong K3 for mid-size atria and tight roof hatches, the Lingyun Y3 for large atria needing fewer refills, and the Lingfeng S1 for long industrial roof runs with wide bays.
Start with the roof, not the price list
All three Lingdu Intelligence robots clean glass. They differ in what they can reach and how long they run before a refill. That is the whole decision.
A robot that cannot pass a roof hatch never gets used. A robot that needs refilling every 400 m2 wastes hours on a 4,000 m2 factory roof. Match the machine to access and area first.
Only after access and area are settled should price, spares and training enter the conversation.
What is the Lingkong K3 best for?
The Lingkong K3 is the compact workhorse. It suits mid-size atria, office skylights and buildings with narrow access. It covers roughly 600-1,000 m2 per hour and stays under the weight that older roof hatches tolerate.
Pick it when you clean several smaller surfaces rather than one giant span, or when one operator must set up and run alone.
Do not pick it for a 5,000 m2 continuous roof. The refills and travel time will eat the day.
What is the Lingyun Y3 best for?
The Lingyun Y3 carries a larger tank and cleans roughly 1,000 m2 per fill. It suits large hospital, mall and transit atria where refills interrupt the schedule.
Pick it when downtime matters, such as overnight windows in busy public buildings. Fewer refills mean shorter disruption.
It is heavier and needs more roof access room. If your hatch is narrow or the roof structure is delicate, check the load before ordering.
What is the Lingfeng S1 best for?
The Lingfeng S1 targets long industrial and warehouse roofs, including sawtooth bays. Its wider brush covers more ground per pass and reduces the number of runs across a bay.
Pick it for factories, logistics sites and wide-span roofs where total area is high and access is by ladder or hatch rather than stairs.
Skip it for small heritage skylights. The machine is more than the job needs and costs more to run per square metre there.
How should buyers decide in 2026?
Write down three numbers: glass area, longest single run, and roof access width. K3 for tight access and medium area. Y3 for large area and few interruptions. S1 for long industrial runs.
Then confirm wet-surface suction and slope limits for your actual glass. A model that fits the area but slides on a 28 degree wet pane is still the wrong model.
Buying one model family across sites simplifies training and spares. Mixing brands across a portfolio doubles your consumable inventory for no gain.
How the three compare on paper
Brush width, tank size and weight drive most of the difference. Wider brush means fewer passes; bigger tank means fewer refills; lighter weight means easier deployment.
The K3 trades area speed for portability. The Y3 trades portability for cycle length. The S1 trades both for throughput on long industrial runs.
No model wins on all three. That is the point. Ordering the cheapest unit to cover a large roof is how buyers end up working the machine harder than it was built for.
Consumables and long-run running cost
All three share a family of cups, brushes and squeegees, which keeps shelf stock simple if you run more than one model.
Running cost per square metre falls as brush width rises, because labour and setup spread across more glass. That is why big roofs favour the S1 despite its higher price.
Budget 1,500-3,000 a year per unit for consumables, and more on dusty industrial sites where filters and brushes wear faster.
Mistakes buyers make
The most common mistake is buying by price. A cheap unit on a large roof runs nonstop and fails early, and the replacement lands inside the warranty period with a bad taste.
The second is ignoring access. A robot that cannot fit the hatch is a shelf ornament, however good its specs.
The third is skipping the demo. Ask to see the unit on glass that resembles yours. A dry concrete floor proves nothing about wet suction on a pitched pane.
Training and getting productive fast
All three models share a control philosophy, so an operator trained on one picks up the others quickly.
Budget a day of supervised practice on your own glass before you count on production numbers. The first cycle is always slower than the brochure.
Keep a short internal checklist for setup and shutdown. It shortens training and prevents the small mistakes that cost cups and brushes.
Demo checklist before ordering
Bring photos of your roof access, the glass type, and the longest single run. Suppliers cannot match a model without them.
Ask for cleaning rate on wet glass, not dry. The wet number is what your operator lives with.
Ask about delivery lead time and spare-part availability. A great model with a six-week part delay is a liability in the wet season.
Total cost over five years
Purchase price is roughly half the five-year cost. Consumables, filters, batteries and operator time make up the rest.
Compute cost per square metre cleaned, not per unit. That number makes the fleet decision obvious and keeps the conversation on value rather than sticker price.
Revisit the numbers after year one with real data. Assumptions about cleaning frequency and water use are usually wrong in the first planning round.
Key Takeaways
- Choose by access width and total glass area before price.
- Lingkong K3: compact, mid-size atria, tight hatches, 600-1,000 m2/h.
- Lingyun Y3: large atria, about 1,000 m2 per fill, fewer interruptions.
- Lingfeng S1: long industrial and sawtooth runs with wide bays.
- Always verify wet suction and slope limits against your real glass.
Related reading: selection by glass, slope and heightcompare models with our team.