The lights and sounds that mean your Roomba is charging
Your Roomba shows it is charging through a combination of lights and sounds. When the dock is powered on and your Roomba is seated correctly on it, you will see a solid green light on the robot itself — this is the clearest sign that charging is happening. Some models also emit a brief beep or chime when they first connect to the dock, though not all do.
The dock itself may also display a light. On most current models, the dock shows a white or blue light when power is flowing to your Roomba. If you see no light on either the robot or the dock, the dock may not be plugged in, or the connection between robot and dock is not secure.
Key Takeaways
- A solid green light on your Roomba means it is charging; a flashing or amber light means something is wrong with the connection.
- The dock must be plugged into a working outlet and positioned on a hard, level surface away from obstacles for charging to work.
- If your Roomba does not dock automatically, you can place it manually on the dock and watch for the green light to confirm contact.
- Charging time is typically two to three hours for a full battery, depending on your model and how depleted the battery was.
- A Roomba that will not charge usually has a dirty charging contact, a misaligned dock, or a battery that has reached the end of its lifespan.
What each light color means on your Roomba
The light on your Roomba tells you the charging status at a glance. A solid green light means the robot is charging normally and you can leave it alone. A flashing or blinking green light means the robot is trying to charge but the connection is not stable — this usually happens when the robot is not seated squarely on the dock or when the charging contacts are dirty.
An amber or orange light indicates a problem: the battery may be too cold to charge, the dock may not be powered, or there may be an error with the charging system itself. If you see amber, unplug the dock, wait 30 seconds, and plug it back in. If the light stays amber after that, the dock or robot may need service.
Some older Roomba models use different light patterns. If you are unsure what your specific model's lights mean, check the manual that came with your robot or search the model number on the iRobot website — the support pages show light meanings for each version.
How to position your Roomba on the dock correctly
Your Roomba will only charge if it makes solid contact with the dock's charging pins. Position the dock on a hard, level surface — not on carpet or a rug, which can shift and break the connection. Leave at least 1.5 feet of clear space on both sides of the dock and 4 feet in front of it, so the robot can approach and align without hitting obstacles.
When you place your Roomba on the dock manually, push it straight back until you hear a click or feel resistance. The robot's charging contacts (two small metal dots on the underside, near the back) must touch the dock's pins. If the robot is tilted or only partially on the dock, the light will flash amber or green but charging will not happen.
If your Roomba has an automatic docking feature and it is not returning to the dock on its own, check that the dock is plugged in and that the area around it is clear. Some models also need the dock's infrared sensors to be unobstructed — do not place the dock against a wall or in a corner.
Cleaning the charging contacts when the light will not turn solid green
Dust and debris on the charging contacts prevent your Roomba from charging, even when it is sitting on the dock. The contacts are small metal dots on the underside of the robot, near the back wheel. Wipe them gently with a dry cloth or a slightly damp cloth — do not use water directly on the robot.
Also clean the pins on the dock itself. These are usually three metal points inside the dock where the robot sits. Use a dry cloth or a cotton swab to wipe away any dust or corrosion. If the pins look bent or damaged, the dock may need to be replaced.
After cleaning, place the Roomba back on the dock and watch for the solid green light. If it still does not appear within a few seconds, try repositioning the robot slightly forward or backward — sometimes a millimeter of movement restores contact.
How long charging takes and when it is complete
A full charge on most Roomba models takes between two and three hours, depending on the model and how much battery was left when you started. During charging, the green light stays solid. When the battery is fully charged, the light may turn off, dim, or change color — check your manual for your specific model's behavior.
You do not need to unplug the Roomba after it finishes charging. Most modern Roombas have smart charging that stops drawing power once the battery is full, so leaving it on the dock overnight or for days is safe and will not damage the battery.
If charging takes much longer than three hours, or if the robot never reaches a full charge, the battery may be aging. Roomba batteries typically last two to three years before they hold less charge or stop charging altogether. If your robot is older than that and charging is slow, a replacement battery may be needed.
Troubleshooting when your Roomba will not charge at all
Start by checking the basics: Is the dock plugged into a working outlet? Test the outlet with another device, like a lamp, to confirm it has power. Is the Roomba actually on the dock, or just near it? Push it back until you feel resistance and listen for a click.
Next, clean the charging contacts on both the robot and the dock as described above. Dirty contacts are the most common reason a Roomba will not charge. After cleaning, wait 10 seconds and place the robot back on the dock.
If the light is still not solid green, try a hard reset: hold down the CLEAN button on top of the robot for 10 seconds until you hear a beep. Then place it back on the dock. If that does not work, unplug the dock for 30 seconds, plug it back in, and try again.
If none of these steps produce a solid green light, the dock may be faulty, the robot's battery may have failed, or there may be an internal charging error. Contact iRobot support with your model number and a description of what the light is doing — they can tell you whether the dock or robot needs to be replaced.
Frequently Asked Questions
Can I charge my Roomba without the dock?
No. Roombas charge only through the dock's pins — there is no USB port or other charging method. If your dock is broken, you will need a replacement dock to charge the robot. iRobot sells replacement docks separately, and they are model-specific, so check your Roomba's model number before ordering.
Why does the green light flash instead of staying solid?
A flashing green light means the robot is not making full contact with the dock. The robot may be tilted, the contacts may be dirty, or the dock may be on an uneven surface. Clean the contacts, make sure the dock is on a hard level surface, and push the robot straight back onto the dock until you feel it click into place.
Is it bad to leave my Roomba on the dock all the time?
No. Modern Roombas are designed to stay on the dock between cleaning cycles. The charging system stops drawing power once the battery is full, so leaving it docked continuously will not overcharge or damage the battery. This is actually the recommended way to store your Roomba when you are not using it.
How do I know if my Roomba battery is dead and needs to be replaced?
If the robot charges for three hours but the light never turns off or dim, or if it runs for only a few minutes before stopping, the battery is likely worn out. Roomba batteries typically last two to three years. If your robot is older than that and charging is slow or the runtime is very short, a replacement battery is probably needed.
What if the dock light is on but the Roomba light is not?
The dock light being on means the dock has power, but the robot is not connecting. Check that the robot is actually seated on the dock and pushed all the way back. Clean both the robot's charging contacts and the dock's pins. If the robot still does not show a light after cleaning and repositioning, the robot's charging circuit may be faulty.