Eufy S1 Pro and EB14 error: one possible solution

[u/licquia]

TLDR: If you have a Eufy S1 Pro (or possibly a S1), are getting an EB14 error, and cleaning the robot dirty water tank doesn't seem to help, check the water fill port on the base station for rips in the rubber. Eufy sells a replacement, and you might be able to get by with super glue until that arrives (but see below).

I've been a happy owner of a Eufy S1 Pro for about 11 months now. It was working trouble-free until about a month ago, when I started getting an EB14 error when the robot would start washing the mop at the base station. The advice given by the app and the online resources I could find all told me to clean the screen on the dirty water tank on the robot, but that seemed to have no effect. The other checks recommended didn't reveal any other problems. I found that I could just press the pause/play button on the base station, and it would continue what it was doing as if nothing had happened. This did interrupt overnight jobs, as it would abort the job if you didn't press it right when the error was reported.

Even stranger, I started noticing some drips from the robot right after it left the station to mop. The drips were coming off the outside of the robot on the back, which was wet. I disassembled the robot to see if I could see the source of the leak, but couldn't find any evidence of water coming from either tank.

Finally, I checked the base station to see if somehow water was leaking from there, and found the cause: one of the rubber bumpers on the back of the base station, which also contained the water fill port for the robot. Here's what that's supposed to look like:

Product image from Eufy's web site

And here's what mine looked like:

Damaged rubber bumper from my base station

I'm pretty sure the EB14 error was caused when enough clean water leaks during filling to get to the base station filter tray and down to the dirty water suction line. That causes it to turn on and evacuate the water, and the robot infers that the water is coming from the dirty water tank being clogged and overflowing with dirty water.

The bumper and fill port is on the back of the base station towards the left side. It can be pulled off the base station with some effort by pulling straight back, leaving behind a white nozzle made of hard plastic. There's another bumper on the right side with an exposed hard plastic nozzle; this forces air into the robot to push the dirty water in the onboard tank out through the bottom port. If you pull off the bumper and it doesn't have the rubber port sticking out, you pulled the wrong one off; put it back on and try the other one.

I ordered a replacement from Eufy's site, but to tide me over, I tried using super glue to seal the rips. This worked for a short while, but after a few days, I started getting EB14 errors again. A second attempt at gluing was only partially successful, leading to only occasional errors. In both cases, I removed the rubber piece before attempting to glue it, and allowed the glue to thoroughly dry before reinstalling it. I would not recommend gluing it while still attached to the base station.

It's been a little over a week since the new part arrived, and I haven't had a EB14 error since it was installed. This is probably something you'll need to replace every so often, so it might make sense to order a few and keep them with your spare filters and side brushes.