How to Keep a Robot Vacuum Running Well for Years
Almost every 'my robot vacuum got worse' complaint traces back to maintenance that was skipped for a month.
A robot vacuum does not degrade gracefully. Its performance falls away slowly enough that owners blame the machine rather than the maintenance, and by the time the suction feels weak the problem has usually been building for weeks.
The good news is that the whole routine takes a few minutes a week, and knowing which parts wear out tells you what to keep in the cupboard.
The weekly five minutes
Flip the robot over and look at the underside. Hair wrapped around the main brush is the single most common cause of reduced pickup and of the burning smell people report. Most brushes have a removable end cap or a groove designed for a cleaning tool, and the hair comes off in one piece if you cut along it rather than pulling.
Check the side brush too. A splayed or bent side brush flicks debris away from the intake instead of into it, and on many models the brush is a cheap replaceable part that should be swapped rather than straightened.
Then empty the bin. If you have a self-emptying dock this is less frequent, but the dock's own bag or bin still fills and still needs checking — a full dock bin means debris backs up into the robot.
Filters: wash them, but know when to stop
Most washable filters are good for a set number of washes rather than indefinitely, and the manufacturer's manual states the interval. Washing more often than recommended is not better — the filter media degrades with handling, and a filter with worn media lets fine dust straight back into the air.
When you wash one, let it dry completely before refitting. A damp filter restricts airflow, which reduces suction and can push dust into the motor housing. Overnight on a rack is the safe option; a radiator is not.
If you have allergies, this is the part to be strict about. A clogged filter on a vacuum without a sealed system is the mechanism by which a vacuum makes air quality worse rather than better.
Sensors and charging contacts
Navigation faults usually start as dirt. The LiDAR turret on top, the cliff sensors underneath and the camera window on the front all need wiping with a dry microfibre cloth — not a wet wipe, which can leave residue that scatters the sensor's beam.
The charging contacts on both the robot and the dock collect a film that stops the machine charging reliably. A pencil eraser or a dry cloth takes it off. If your robot has started returning to the dock and then not charging, this is the first thing to check.
Wipe the bumper edges too. On camera-based models the front-facing lens sits behind plastic that scratches easily, so use a soft cloth and avoid paper towel.
If it mops, the mop is a separate maintenance job
Mopping pads need washing after every use and replacing on the schedule in the manual. A pad left damp in the dock grows bacteria, and that is the source of the smell people notice after a few weeks of mopping.
Water tanks should be emptied rather than left filled between runs, and only the manufacturer's recommended cleaning solution should go in. Third-party solutions can foam inside the pump and cause damage that is not covered. On models with a rotating mop, the mop pads and the water delivery system each have their own maintenance interval — check both.
What to keep in the cupboard
The parts that genuinely wear out are the main brush, the side brush, the filter, and on self-emptying docks, the dock bag. Keeping one spare of each means a worn part is a two-minute swap rather than a week of degraded cleaning while you wait for a delivery.
Buy the manufacturer's own consumables where the part is mechanical. Third-party brushes vary considerably in bristle stiffness and hub tolerance, and a poorly fitting brush can damage the brush motor. Filters are less risky, but check the stated filtration rating rather than assuming all filters for a model are equivalent.
Finally, log the date you fit a new part. Wear is gradual and you will not notice it happening, but you will notice the difference when a fresh brush goes on.
Products mentioned in this guide
Products referenced in this guide, shown with the manufacturer's own photography. We do not publish prices or star ratings — both change faster than any article can be kept accurate.
Robot Vacuums
Roborock S8
- Dual rubber main brushes that resist hair tangling
- 6,000 Pa suction with a sonic mopping pad
- LiDAR navigation with multi-floor map storage
Works with
- Alexa
- Google Home
- Roborock app
Robot Vacuums
Eufy RoboVac 11S
- Bump-and-roll navigation with no camera or LiDAR
- Very quiet for a robot vacuum
- Physically slim, so it fits under low furniture
Works with
- Remote control only
Frequently asked questions
How often should I replace the main brush?
It depends on hair volume and floor type rather than a fixed calendar. Inspect it weekly: once the bristles are visibly shorter, flattened or frayed at the ends, the brush is no longer sweeping effectively and should be replaced.
Why does my robot vacuum smell?
Almost always the bin, the filter or a damp mop pad. Empty and rinse the bin, wash and fully dry the filter, and wash the mop pad after every use. If the smell persists after all three, check the brush housing, where hair and dust accumulate out of sight.
Can I use any cleaning solution in the water tank?
Use only what the manufacturer specifies. Foaming and abrasive solutions can damage the pump and internal seals, and damage from unapproved solutions is commonly excluded from warranty cover. Plain water is the safe default.