AquaStop is a leak-protection system built into Bosch washers and dishwashers, designed to detect water where it shouldn’t be and shut off the water supply automatically. When it triggers — showing as E23 on washers or E15 on dishwashers — it’s worth understanding what’s actually happening.
It’s a Feature, Not a Bug
AquaStop exists specifically to prevent the kind of slow, undetected leak that can cause serious water damage to flooring, subfloors, and cabinetry long before a homeowner notices. A triggered alert means the system did its job.
The Right Response
Turn off the water supply valve to the appliance immediately, and don’t attempt to reset and rerun a cycle to “see if it clears.” Even if the trigger turns out to be a false alarm from a stuck float switch, running the appliance again before confirming that is an unnecessary risk.
Real Leak vs. False Trigger
Both washers and dishwashers can occasionally show a false AquaStop trigger from condensation or a worn float switch — but distinguishing a false alarm from a real leak reliably requires a technician’s inspection, not a guess.
Bottom Line
Treat every AquaStop alert as a genuine leak until proven otherwise. It’s a small inconvenience compared to the water damage it’s designed to prevent. Book a visit through our washer or dishwasher repair pages.
Not Confident Doing This Yourself?
A factory-trained technician can diagnose and fix it safely, usually same-day.