It stopped cleaning well
Suction loss is almost never the motor. Work through these five in order.
The machine runs its full cycle, returns to the dock, and the floor still has crumbs on it. This is one of the most common complaints and one of the most fixable — it is nearly always maintenance rather than a fault.
The five checks, in order
1. The filter. Start here. A clogged filter chokes airflow and reduces effective suction more than any specification difference between models. Tap it out, wash it if washable, replace it if not. If you cannot remember the last time you did this, this is your problem.
2. The main brush. Remove it entirely. Hair wraps around the ends where the bearings sit, which slows or stops rotation. A brush that does not spin freely by hand is not agitating your carpet, and the machine gives no warning about this.
3. The side brushes. These bend over time and stop reaching the floor. They are cheap and easy to replace, and they are what pulls debris from edges into the machine's path.
4. The bin and its seal. An overfull bin reduces airflow. So does a bin seal that has hardened or come loose — air takes the easy path and bypasses the filter entirely.
5. The wheels. Hair wraps around wheel axles, which makes the machine drag, slow down and cover less ground per charge. Check the small front caster in particular.
If all five are clean
Then consider these:
- Battery degradation. Shorter runs mean less coverage, which looks like worse cleaning. If runtime has dropped noticeably from new, the battery is the cause, and on most models it is replaceable
- A changed map. New furniture or a moved sofa can leave areas unrouted. Re-run mapping
- Suction setting. Apps sometimes reset to eco mode after an update
- The floor changed, not the machine. A new rug, a shedding season, or a pet growing its winter coat all increase the load
The maintenance interval that prevents this
| Weekly | Monthly | Quarterly |
|---|---|---|
| Empty bin, clear brush hair | Wipe sensors, check wheels | Wash or replace filter |
Ten minutes a month prevents nearly all of the complaints in this article, and it is also the difference between a machine that lasts three years and one that lasts eight.
If maintenance is up to date and it still underperforms, the machine may simply be past its useful life. See vacuum cleaners → Advertising — we may earn a commission.
Common questions
Why has my robot vacuum lost suction?
Almost always a clogged filter, followed by hair wrapped around the main brush or wheel axles. Check the filter first — it reduces effective suction more than any specification difference between models.
How often should I clean a robot vacuum filter?
Every two to four months, or sooner in a pet household. Washable filters can be rinsed several times before performance drops; non-washable ones must be replaced on schedule.
Is worse cleaning a sign the battery is failing?
It can be. A degraded battery means shorter runs and less coverage, which looks like worse cleaning. If runtime has dropped noticeably from new and maintenance is up to date, the battery is the likely cause and is usually replaceable.