Ecovacs Deebot N79S Robot Vacuum Feels Like the Future

Robot vacuum cleaners may seem like futuristic technology to many of us, but they’ve been around since 2002, starting with iRobot’s Roomba. When the Ecovacs Deebot N79S went on sale for $180 recently—it usually sells for $250—I hopped on the figurative flying car. Now that I have one, I’m wondering how my family survived so long without it.

The Deebot N79S is a round disc on wheels that weighs about 5 pounds (2.34 kg). It’s roughly 12.5 inches (32 cm) in diameter, and is about 2.25 inches (5.7 cm) tall, making it low enough to slide under many pieces of furniture, including most chairs, some coffee and end tables, and some couches. The Deebot N79S is a newer and slightly more advanced version of the Deebot N79 with a more-powerful cleaning option that I never use and Alexa support that’s basically pointless. I refer to them interchangeably here unless I mention an N79S-specific feature.

Why did I choose a model from Ecovacs, a relatively unknown company, over one of the more well-known Roomba models? Even at its list price of $250, the Deebot N79S is cheaper than the low-end Roomba 690, which goes for $300 on Amazon, and the Deebot N79S is often on sale for under $200. The Deebot N79 is a little cheaper yet, and it too often receives discounts that drop its price well under $200 on Amazon, making it one of the cheapest robot vacuums on the market. Despite the low cost, the Deebot N79 is Wirecutter’s current top pick for a robot vacuum.

Wirecutter thinks that the Roomba 690 will likely last a few years longer, due to a more proven design. That’s something to consider if you’re in the market for a robot vacuum, and if the price delta is only $50 when it’s time to buy, you should look at the Roomba. But if you can pick one up for as low as $150, the Deebot N79 is a steal.

Price is one reason many people never give a robot vacuum a chance. Before the Deebot, the typically recommended Roombas were $300 or more, and a decent canister or upright vacuum could be had for $150 or well under that. It’s also hard not to be skeptical of the technology in general. Vacuuming by hand is tricky enough—making sure you’re not sucking up things you shouldn’t, moving chairs and rugs out of the way, and navigating tight spots—that I didn’t think a robot could handle the job. Surely the people who loved these machines didn’t have children or pets, and were somehow capable of keeping their floors free of junk and debris.

So how does it work?

AI and Engineering

I must say up front that watching Deebot N79S will drive you bonkers. It goes over the same spot repeatedly, gets stuck in a makeshift obstacle course that wouldn’t even slow down a self-respecting rat, and wanders the entire house trying to find its charger when it’s a foot away. Is this how managers of the future will feel watching their robot employees work?

The Deebot’s AI may rely on a path-planning algorithm that seems dumb—it’s highly intentional, in fact—but the engineering behind the Deebot is smart. Two long spinning brushes on opposite sides of the typical vacuum brush roller help sweep dirt into the robot’s mouth, which helps maximize how much dirt it picks up. Anti-collision and anti-drop sensors keep it from slamming into walls and other objects, or, as you can see in my short video, from careening down the stairs.

One of the best little bits of engineering in the Deebot is its suspension, which lets the robot body easily navigate small changes in height or pick up larger objects. My son has a Nerf obsession, so I often find several darts when I empty the Deebot’s dustbin.

For the most part, it also transitions well from hard floors onto carpets and vacuums them without much fuss. Be aware that the Deebot is intended only for hard floors and short carpet. Shaggier carpets can bog the Deebot down, though it works acceptably on the medium-plush carpet we have upstairs.

I’m especially impressed with how well it handles lightweight bathroom rugs, which are nearly impossible to clean with a traditional vacuum. It does sometimes get stuck trying to suck up the corner of a rug, but those rugs are still getting vacuumed more than they would otherwise.

Overall, though, the Deebot gets the job done. After letting it work for a few days, the house is visibly cleaner and there is less observable dust in the air. I haven’t felt the need to pull our old vacuum cleaner out of the closet for the past month.

Running the Hoover

Using the Deebot is as simple as pressing its single button, labeled Auto. The Deebot starts vacuuming, and about 2 hours later, when the battery is low enough, it makes its way back to its included charging dock and prepares for its next cleaning session.

The first thing to figure out is where to place that dock. Putting it under a tall, wide chair confused the Deebot, so I instead opted for a fairly open corner in front of a bookcase. The reality is that the dock will probably be in your way, because it needs to be easy for the Deebot to find.

Needless to say, the Deebot can’t navigate stairs, so if your house has multiple levels, you’ll need to move it manually or consider purchasing one for each floor. The Deebot is light enough that I just haul it upstairs every few days to vacuum our low-traffic bedrooms. As the video above shows, it’s good about not plummeting to its doom. Unfortunately, it won’t do anything to keep your stairs cleaner, so that’ll be one place you’ll still have to vacuum by hand.

The Deebot may have only one button on the unit itself, but it has a remote with many more. You only need the two at the top—the Auto button and the other one to return the Deebot to its base.

Using the remote, you can enable a variety of modes for spot cleaning, cleaning a single room, and cleaning the edges of a room, the last two of which are largely unnecessary. If I want to clean just a single bedroom, I put the Deebot down, press Auto, and shut the door on my way out. When I come back a few hours later, the floor is clean.

Spot cleaning is more useful, in case you spill something in the middle of a large room that’s otherwise clean, or you can use the remote’s directional buttons to take manual control. That capability came in handy the other day when I accidentally tracked freshly cut grass into the kitchen and didn’t feel like pulling the big vacuum out of the closet, unwinding the cord, finding an open outlet, and putting it all back when I was done.

The Ecovacs iOS app is best described as “adequate,” mostly because it’s painfully slow, taking up to a minute to connect to the vacuum. I can’t recommend it generally, but it has a few uses:

• Viewing error messages when something goes wrong.
• Programming a schedule, though this can also be done via the remote.
• Checking the estimated remaining lifespan of consumables such as the paper filter.
• Adjusting the suction power of the vacuum on the N79S. There’s no reason to do this because it shortens the battery life so much that the increased suction makes no difference in the eventual amount of dust collection.

The best way to set up the Deebot is to give it a schedule and just let it do its thing. I let mine run at 7:15 AM every weekday, just after my wife and son have left the house. At 64 decibels, it’s relatively quiet, but you won’t want to run it when you want silence.

If you work outside the home, you will likely want to run the Deebot while you’re away, but that can be a mixed bag. I often turn it on when I’m heading out the door, and most of the time I come back to it having done its duty and returned to the charging dock. (It’s unfortunate that it doesn’t support HomeKit, because then I could set it to start cleaning when I leave the house and stop when I arrive home.) Most days, the Deebot needs no assistance, but sometimes I get home to find it hung up. It can have trouble with:

• Window shade cords, power cords, or any sort of string that can get wrapped around the Deebot’s roller
• Objects of a certain size—my 4-year-old once spread a bunch of small screwdrivers on the floor, and that really tripped the Deebot up
• Lightweight rugs that can bunch up under the Deebot, especially if they have tassels or frayed edges
  

Happily, all of these little things are easy to fix. The bad news is, if you’re not home to do so, these errors can seriously cut into your automated cleaning time.

Regular Maintenance

Most of my active time with the Deebot is in doing some basic maintenance to keep things running smoothly. These tasks include:

• Picking up small objects that will give the Deebot a hard time, like cords, small screwdrivers, and other things small enough to get sucked into the Deebot but too big to be captured successfully. Your floor doesn’t have to be perfect—the Deebot successfully navigates around all sorts of junk in our house.

• Picking up rugs that I know will give Deebot trouble or tucking in frayed edges. I don’t even need to do this much; the Deebot seems to figure out how to avoid these.
• Wiping down the sides of the Deebot every few days to keep the sensors clean. If they get too dirty, the Deebot can stop working entirely.
• Emptying the dustbin every day, and cleaning the filters every few days. These are the most important tasks.

Even cleaning the entire system takes no more than about 5 minutes. I dump the dustbin in the trash, remove the paper high-efficiency filter and shake it out, and rinse the sponge filter and filter net under a faucet. Ecovacs also recommends cleaning the brushes, but I do that only when there’s a problem. I then dry the sponge filter and filter net with a paper towel and let them finish air-drying. Sometimes I rinse out the dustbin, but if it’s not too dirty, I just wipe it out with the damp paper towel.

The Deebot comes with a neat little cleaning tool with brushes and various implements to remove tangles. The main tangle cutter is basically a letter opener—I wish I’d thought of that before for removing hair from our old vacuum’s roller.

Ecovacs recommends replacing the paper filter every 4–6 months, which seems reasonable. But the company also recommends replacing the side brushes twice per year and the main brush once every year. That seems wasteful, but we’ll see how they hold up.

Rosie the Robot

I’ve been writing about home automation gizmos for a while—I even wrote Take Control of Apple Home Automation about the topic—but the Deebot is the only one that continually amazes me on a daily basis. Robot vacuums aren’t at all new at this point, but there’s something about the physical nature of it that makes it feel futuristic. Maybe that’s due to all the time I spent watching The Jetsons as a kid.

Speaking of that futuristic element, I would be remiss if I didn’t at least mention the Deebot’s Alexa integration. It’s mostly a gimmick because you’re better off setting a schedule, but it works well enough. I can say to my Ecobee thermostat: “Alexa, tell Deebot to start vacuuming” or “Alexa, tell Deebot to charge.” and it will do so (see “A Prairie HomeKit Companion: The Ecobee 4 Thermostat,” 20 April 2018). Something about talking to my thermostat to control my vacuum greatly amuses me. Voice control may not be particularly useful when it comes to cleaning the carpet, but it’s a reminder of how far we’ve come from the days of scrubbing the floor on hands and knees.

Gimmickry aside, the Deebot N79S is a legitimately useful gadget, and if you’re unhappy with the amount of time you spend vacuuming your house, and particularly if you’re in the market for a new vacuum anyway, check it out.