my braava m6 isn't spraying any water. the tank is full and it's moving around but the floor is dry.

Diagnosis

The Braava Jet M6 relies on a pressurized pump system to push water from the tank through a narrow Precision Jet Spray nozzle. When the robot moves but the floor remains dry, the issue is almost always a physical blockage in the spray orifice or an airlock in the internal plumbing. Because the M6 uses a very fine nozzle to create the mist, even a tiny amount of mineral buildup from hard water or a stray piece of lint can completely seal the exit point. Another common cause is a vacuum seal failure. If the tank cap isn't seated perfectly or the rubber gasket is pinched, the pump cannot create the necessary suction to pull water from the reservoir. In some cases, if the robot has been sitting idle for several weeks, the water in the internal lines may have evaporated, leaving behind a concentrated salt or mineral crust that blocks the flow. You can confirm a clog if you hear the pump humming (a faint, high-pitched buzzing) during a cleaning cycle, but no mist is visible emerging from the front of the chassis.

How to Fix It

Follow these steps in order to clear the system and restore water flow:

1. Verify Pad Type: Ensure you are using the official Braava Jet M6 Wet Mopping Pads. Dry pads are thicker and can occasionally obstruct the spray path or absorb the water too quickly for you to notice the spray.
2. Clear the Nozzle: Locate the Precision Jet Spray nozzle on the underside of the robot. Use a damp, lint-free microfiber cloth to wipe the nozzle clean. If you see visible crusting, dip a cotton swab in a mixture of 50% white vinegar and 50% distilled water and gently scrub the nozzle opening. Do not use needles or pins, as you can permanently damage the aperture.
3. Reseat the Tank: Remove the water tank. Inspect the rubber O-ring on the cap for any cracks or debris. Re-insert the tank and press down firmly until you feel it click into place. A loose tank prevents the pump from creating a vacuum.
4. Adjust App Settings: Open the iRobot HOME App. Navigate to the "Cleaning Preferences" menu. Ensure the "Water Level" is set to "High" for testing purposes. If it was set to "Low," the robot may spray so infrequently that the floor appears dry.
5. Prime the Pump: With the tank full, run a "Clean Edge" cycle. This forces the robot to spray more frequently along the perimeter, which can help push an airlock through the system.

If That Didn't Work

• Perform a Hard Reset: Power the robot off completely by holding the CLEAN button for 10 seconds until the lights go out. Wait 30 seconds and power it back on. This resets the pump logic and can clear software glitches that prevent the spray trigger from firing.
• Deep Clean the Reservoir: Empty the tank and fill it with a solution of warm distilled water and a drop of white vinegar. Let it sit for 30 minutes, then attempt a cleaning cycle. The acidity of the vinegar helps dissolve calcium carbonate deposits inside the internal tubing that a surface wipe cannot reach.
• Check for Leaks: Inspect the bottom of the robot for any pooling water. If the pump is working but the water is leaking internally rather than spraying, you may have a cracked internal hose, which requires professional repair.
• Test with Distilled Water: If you have been using tap water, switch to 100% distilled water. If the spray returns, your local water hardness is the culprit, and you must avoid tap water to prevent future clogs.

Heads Up

• Avoid Third-Party Chemicals: Never use bleach, ammonia, or thick floor cleaners in the tank. These can corrode the internal pump seals and clog the nozzle with residue that cannot be cleaned.
• Empty After Storage: If you do not plan to use the M6 for more than two weeks, empty the tank and run one final cycle to clear the lines. This prevents mineral buildup from hardening inside the pump.
• Use Distilled Water: To maximize the lifespan of the Precision Jet system, use distilled water exclusively. This eliminates the "white crust" buildup that causes 90% of spray failures.
• Pad Saturation: If the pad is bone-dry at the start, the first few sprays may be absorbed instantly. Lightly dampen the pad with a spray bottle before starting the robot to verify the spray is actually working.