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Product test

Why the iRobot Roomba S9+ doesn’t quite rule my world

Kevin Hofer
16/11/2021
Translation: Veronica Bielawski

The promise of a robot vacuum cleaner is awesome: kick your feet up while the robot does all the dirty vacuuming work for you. That’s the theory. In practice, things look a bit different.

Since moving in July of this year, I’ve been flirting with the idea of getting a robot vacuum cleaner for our family of four. My wife is against it. On the one hand, because she thinks they don’t do a good job cleaning, and on the other because she doesn’t trust them. She fears the robots are out for world domination.

Quick set-up, long prep time

The S9+ comes with a dock that simultaneously charges the robot and empties its bin. It promises to spare me manual vacuuming for months at a time. The scope of delivery also includes a replacement bag and filter, as well as a brush.

If you want to know what other features make the Roomba S9+ stand out, I recommend you watch iRobot’s video below. In this review, I prefer to focus on my actual experience using the S9+. After all, this robot has been around since 2019, and there are plenty of reviews out there that focus on technical data and features.

I set up my Roomba S9+ in the iRobot app. It’s easy to do and takes just five minutes. I can even name my robot – it shall henceforth be known as Robby. What I’m less enthused about is the fact I have to create an iRobot account. But according to the manufacturer, an account is necessary if I want to control Robby over the cloud using my phone. Hurrah – another account somewhere containing all my data. Oh well. The vacuum cleaner is ready for duty! ...Or is it?

World domination? Yeah, no

There are two prerequisites for Robby's vacuuming to be successful: A) the kids can’t be home, because they make a mess with their every step and get in Robby’s way; and B) I have to do some preliminary cleaning. In practice, this means I can only run the vacuum cleaner when I’m home alone. Luckily, I’m reviewing the S9+ for work. Otherwise, what I spend my working hours on could be deemed questionable...

At first, Robby requires a fair bit of my attention. He needs to get settled in our home, i.e. create a virtual map of the apartment so he knows where everything is. This takes several cleaning cycles. In my case, three – the first sign that Robby isn’t the sharpest tool in the shed. Over the next six weeks, I come up with five more reasons why vacuum cleaner robots couldn’t possibly take over the world.

Reason #1: radiators

Radiators kill vacuum cleaner robots – or at least put them out of commission. During his first mission, Robby drives under a radiator and gets trapped. Fortunately, the app alerts me to this. I free him from his predicament, and he continues cleaning. It seems Robby has memorised this danger zone, as he doesn’t trap himself there during any further cleaning cycles. Regardless, this first attempt at world domination is a fail.

Reason #2: doors

Here’s something I thought only my kids did: shortly after getting trapped under the radiator, Robby locks himself in a room. He had managed to push the door shut while cleaning. Robby can push, put he can’t pull. So, he gets stuck again. The app notifies me of this, too. I try my luck with doorstops, but Robby just pushes them away. I end up with a different solution, which I discover in his next failed attempt to conquer the world.

Reason #3: door thresholds

Reason #4: children

Reason #5: grime

Robby himself isn’t immune to grime, either. After about two weeks, I want to start him up in the app while I’m out. Unfortunately, no connection can be established. What’s the matter now? It’s Saturday; the whole family is out shopping. I have to earn the privilege of going home alone to clean the bathroom and kitchen – unfortunately Robby’s of no help there, either.

Back home, I discover Robby has no juice left, despite being at the charging station. And the charging station is plugged in... I turn him around and realise Robby’s a bit dirty. Some grime, possibly dried jam, has deposited on his charging contacts. Hey, I did mention that the area around the table tends to get the dirtiest. I clean the contacts and put Robby back on the charging station. Success! Guess I’ll clean the kitchen and bathroom while Robby charges...

After a few minutes, he awakens. He drives off the charging station. Then attempts to drive back onto it. What in the world? He doesn’t quite succeed; instead, he briefly docks and then tries again. This goes on until his battery’s dead. Robby is stuck in an endless loop.

I can’t turn him off in the app. The only option I have is to reset him to factory settings. After the reset, the map Robby had created of my apartment is gone. So, he has to remap everything from scratch. Well, that’s annoying. Luckily, the issue doesn’t repeat itself throughout the remainder of the testing period.

How good is the suction?

What I can say is my wife’s second objection doesn’t hold water: when Robby vacuums, he vacuums well. Thanks to his half-rounded shape and corner brush, he has no trouble getting into the corners and edges of a room. And he picks up not only dust, but also larger bits like bread crumbs. After each cleaning cycle , the carpets are clean with no debris left.

One cleaning cycle in our 5.5-room apartment (roughly 125 square metres) takes around two hours. Robby typically runs out of battery before he’s done and has to briefly recharge to complete the cycle. However, I’ve noticed the time needed decreases a bit with each cycle as Robby gets to know the apartment better and better. Maybe in a months’ time, one charge will do for a full cycle.

The fact that Robby has no mopping function isn’t a dealbreaker for me. Because I have unsealed hardwood flooring in the living area and cork flooring in the bedrooms, I don’t want to get excessive moisture on it and prefer to mop it myself.

Verdict: not it for a family like mine

Despite his flaws, I like Robby the Roomba S9+. He’s good at vacuuming and easy to use. For neat singles and childless couples, the S9+ works well.

But for my use case, the S9+ just isn’t it. Vacuuming my apartment by hand takes 20 minutes – if I prepare my apartment the way I do for Robby. This is time consuming in and of itself: depending on the mess, it takes me anywhere from half an hour to forty minutes. And then Robby still needs two hours to vacuum. So, he hardly saves me any time.

Not to mention that if I overlook something during my pre-cleaning, Robby will break down and I’m forced to intervene. If I’m not home when this happens, Robby remains stuck until I get back, and I’m forced to be present for his cleaning. Without my children, mind you, because they always get in good ol’ Robby’s way. Long story short: with a family, too many factors have to be just right for fully automated cleaning to work.

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From big data to big brother, Cyborgs to Sci-Fi. All aspects of technology and society fascinate me.


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