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Narwal (brand store)What testers say about the Narwal Flow
The Narwal Flow is Narwal's first robot with a roller mop: a flat, track-shaped mop that is sprayed with 113 °F water and scraped clean while it mops, and that moves out sideways towards walls. Beyond that, 22,000 Pa of suction, a floating main brush and side brushes built against hair wrap, obstacle recognition with two cameras, and a lidar built into the back of the body instead of a turret on top, which keeps the robot 3.7 inches tall. It climbs thresholds of up to 1.6 inches. The station empties the bin into a 2.5-liter bag, washes the mop in 176 °F water and dries it with hot air, but adds no detergent by itself: cleaning solution goes into the clean-water tank by hand.
Mopping is where the testers agree. Vacuum Wars measured one of the highest combined mopping scores it has recorded, with less water left behind than average, Tom's Guide saw it clean dried ketchup better than a plug-in steam cleaner, and TechRadar found the mop still looking new after weeks of use. Hair does not wrap: nothing wound around the brush in Vacuum Wars' long-hair test, Tom's Guide rarely had to pull hair off the roller, and on carpet it lifted 83 percent of the embedded sand, against an average of 76 percent. TechRadar and Tom's Guide praise its obstacle avoidance, with a sock, a shoe and a charging cable all dodged in TechRadar's test, and Vacuum Wars measured the best battery efficiency it had seen.
The criticism is about navigation and software. RTINGS found that its route planning skips whole sections, so it left a lot of debris along edges and in corners on hard floors and carpet, and dragged pet hair around instead of picking it up. Tom's Guide also found edge cleaning mediocre and saw it tumble down a kitchen step, and TechRadar watched it spill the contents of its bin, report a room as cleaned without entering it and bury its settings in an app with clumsy translations. For homes with mostly hard floors on one level, where mopping matters most, it is one of the best-mopping robots the testers have seen. Its successor, the Flow 2, adds detergent dosing and 31,000 Pa.