We took our new Roomba S9+ and the previous model of the Roomba I7+ and put them both through a series of tests to see which one was the best and why. And the results were pretty interesting mainly because of how different these models actually are.
Shape
There was a major redesign that the new D-shape on the S9+ was to give it better edge and corner cleaning performance and we did find that it had excellent corner cleaning ability, especially when compared to the I7+, the S9 wasn’t perfect, but it was awfully close.
Brushroll
Irobot made a fundamental change to their side brushes. This super-fast spinning, stiff side brushes on previous Roomba models just caused a major mess most of the time including with the I7+.
So not only is the new brush softer, the speed that it spins is also toned down with the S9+, which makes for a much cleaner pickup, especially on hard floors. Irobot also took the dual brush roll and moved it to the front of the unit and made it wider by 30%. This obviously gives it a wider cleaning path, but it also seems to affect its ability to avoid hair tangles and its carpet deep cleaning ability.
Suction power
We measured S9’s airflow with an anemometer at 22 CFM on high power and 8 CFM on low power beating the previous champion, the Neato D7 by almost 10%.
- The I7 was made to be fully automatic, so we can’t choose a power setting. It adjusts itself, but when it’s on its carpet boost mode, it’s equivalent of high power. It can adjust to 17 CFM the same as the Roomba 980 but on hard floors it seems really low. It seems to have less power on hard floors than the Roomba 600 series which we measured at only 7 CFM.
- The S9 blows away the I7 on the crevice pickup test in which the S9 picked up all the debris from the 8 inch crevice and even some from the quarter inch, but the I7 didn’t get any from either.
Cleaning performance
Sand cleaning
The difference was shown with a sand test on single pass mode and sand is really hard for any type of vacuum to pick up on hard floors.
It can be seen that the S9 did pretty good. There was a little left and various places, but when compared to the I7 which left quite a bit of sand on the floor, the S9 looks like a beast
Carpet deep cleaning
One of the most practical uses for all that power on the S9 is carpet deep cleaning. Here we measure out exactly 100 grams of sand and embedded into medium pile carpet, run the robots for five minutes and weigh the bins.
- The I7+ with its carpet boost mode engaged and the also the Neato botvac got the same score which was 79%.
- The S9+ which were tested twice, got 93% and 96% which is something to really be celebrated.
Hair wrap
The hair wrap test is conducted where we take 1 gram of 7 inch hair and spread it over hard floor. We tested the S9 twice with this and each time it did so much better than other robot vacuum. The I7 pretty much does the reverse.
- I7: Only 25% of the hair made it to the dustbin on the I7, that means 75% was caught in the brush roll.
- S9+: Compare that to the S9+ were 95% of the hair made it to the dustbin, which’s impressive.
Larger debris
The one area where I think the S9 is not as good as the I7 is with large debris pickup, the S9 made some serious racket when picking up the larger piles of debris. It did pick up all the large debris, but it took a couple passes in a few cases to do so. The brushes are probably lower to the ground on the S9 or what, but if so it might explain why it’s so good at deep cleaning carpets, which would be a good trade-off.
Smart navigation
Similarity
Moving on to navigation, both the I7+ and the S9+ our smart navigation robots that use cameras to map out your home and clean and nice roads while avoiding obstacles and while both seem to have excellent coverage as you would expect from a smart vacuum in this price range.
Difference
Time Efficiency
The S9+ is much more efficient with its time. It does kind of a rough draft pass and then goes directly to the places it missed and follows it all up with an edge cleaning pass.
The I7 does the same basic thing but it also seems to waste a lot of time on weird things. For example, it circled around this one chair leg 11 times in one test.
Climbing over obstacles
In fact, when being turned off the automatic pass button and only choose one pass with the I7, it would almost use its entire battery life on this one room.
S9 is also better at climbing threshold. It could pretty regularly climb 3/4 inch board where the I7 is only able to do it if it hits it just right.
Battery
Similarity
In terms of battery life, they both have recharge and resume where they will return to the base to recharge and then resume where they left off.
Difference
The I7 on its one power setting gets about 75 minutes
The S9 can get a range between 120 and 50 minutes depending on how you choose to adjust the power output.
Self-emptying bin
Similarity
So the best thing about either of these robots might be that it has a clean base. This is the self-emptying bin system, which while has been attempted before Irobot is the first to perfect the system. It’s not that the old system of emptying bands after each use was such a chore, but it didn’t really feel like we had a robot doing our work for us, but the clean base really makes that dream seem possible and it functions well.
The suction motor in the clean base is really powerful and does suck out all the dirt and hair and whatnot and the bags really do seem to hold about 30 bins of debris, but that really depends on what kind of debris you’re picking up.
Difference
With the I7, the clean base was the reason to get the I7+, but as we’ve seen, the robot itself wasn’t that great.
The S9+ they’ve paired a trend-setting top-of-the-line robot to their new clean based technology and though this thing costs a ton of money, Irobot is finally delivering some real value for what they’re charging.
Verdict
The S9 is Roomba’s most powerful robot vacuum and it might be the most powerful robot vacuum on the market right now.
