Robot vacuum cleaner Xiaomi does not supply water to the cloth: 7 reasons and how to fix

Have you started cleaning and Xiaomi's robot vacuum cleaner (or Mi Robot Vacuum, Viomi, Dreame) ignores the wet cleaning function?The rag remains dry even though the reservoir is full of water and there are no bugs in the Mi Home app? This problem is found in models with a wet cleaning system - from the budget Xiaomi Mi Mop 2 Pro to the flagship DreameBot L10s In 80% of cases, the fault can be fixed independently without contacting the service.

We analyzed the feedback from owners, service manuals and technical schemes to provide a complete guide to diagnostics and repairs.

• 🔍 Checklist of 7 reasons why the robot does not supply water (from banal clogging to pump breakdown).
• 🛠️ Step-by-step instructions with photos and videos for disassembling and cleaning key nodes.
• ⚠️ Typical mistakes that make the problem worse (such as using unoriginal rags).
• 📊 Comparative troubleshooting table for popular models Xiaomi and Dreame.

If your robot vacuum cleaner has stopped moisturizing the floor, don't rush it to the workshop, and in most cases, just clean the valves, replace the sealing gums, or reset the settings to the factory, and let's start with the simplest thing: checking for obvious reasons.

1. Check basic settings and preparation for cleaning

Before you disassemble the robot, make sure that the problem is not software settings or improper preparation, and 30 percent of the time, the water is not supplied because of trivial user errors.

Open the Mi Home app (or Dreamehome for Dreame devices) and check:

• 📱 Cleaning mode: whether wet cleaning or wet wiping (not just dry cleaning) is chosen).
• 💧 Water supply level: may be set minimum level (Low), and there is not enough moisture to soak the cloth.
• 🔄 Cleaning schedule: Some models turn off water supply at night to save charge.

Also check out the physical elements:

• 🚰 Water tank: It should only be filled with clean water (no detergents!) and tightly installed before clicking.On some models (e.g. DreameBot) L10s Ultra has a water level sensor – if it is contaminated, the robot “thinks” the reservoir is empty.
• 🧽 Cloth: It must be original (or size compatible) and properly secured to the holder.

⚠️ WARNING: If you use detergents or flavors in a tank, it can lead to clogging of valves and tubes. Xiaomi officially forbids adding anything other than water!

Check the water level in the tank.|

Make sure you select a wet cleaning in the application|

Clear the tank contacts from the raid|

Use only the original rag.|

Reset the water supply settings to factory (in Settings) → Recovery)

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2.Clogging of the water supply system: how to clean the valves and tubes

The most common cause of lack of water is clogging of valves, filters or tubes.

• 🧂 Hard water (formation of lime plaque).
• 🧴 Use of detergents (sludge clogs small holes).
• 🐭 Dust and debris entering the system when water is replaced.

For cleaning, you will need:

• 🔧 Screwdriver (usually) T5 or T6 Xiaomi).
• 🧴 Citric acid or vinegar (to remove plaque).
• 🪣 Warm water and a soft brush (such as a toothbrush).

Step-by-step instructions for cleaning:

1. Remove the water tank and rinse it with warm water. Check the intake valve (the small hole at the bottom) - it often clogs.
2. Unscrew the bottom cover of the robot (usually 4-6 screws), under which you will see a pump and water supply tubes.
3. Unplug the tubes and rinse them (you can use a bicycle pump). If the clog is severe, soak the tubes in a solution of citric acid (1 tbsp. spoon per 1 liter of water) for 30 minutes.
4. Check the electromagnetic valve (located next to the pump) and it should click when you give the cleaning command. If there are no clicks, the valve is faulty.

For models with a self-cleaning base (for example, DreameBot) L10s Ultra or Xiaomi S10+) check in:

• 🔄 The condition of the base rollers - they can be clogged with hair and threads.
• 💦 Fine cleaning filter (usually hidden under base cover).

3. Pump malfunctions: how to check and replace

If you still don't get water after cleaning, the problem may be a faulty pump.

• 🔇 The pump does not emit vibration or hum when wet cleaning is turned on.
• 💡 The app appears with a Pomp error not responding or Error 12 (for Dreame).
• 🔌 The pump is working, but water is not coming in (may indicate a pipe break or impeller breakage).

How to check the pump:

1. Connect the robot to charging and turn on the wet cleaning mode.
2. Apply your ear to the bottom of the body – a light hum (a working pump) should be heard.
3. If there is no hum, disable the robot and disassemble it (see instructions above).

Critical information: The pump in Xiaomi and Dreame robot vacuum cleaners is not repairable - only replaceable.Average cost of a new pump: 1,500-3,000 ₽ model-wise.

If you decide to replace the pump yourself, follow these tips:

• 🛒 Buy a pump with the original item only (for example, for Mi Mop 2 Pro this is the first one). ZNMS18WM).
• 🔌 Before installing a new pump, check the polarity of the connection – the wrong connection can burn the control board.
• 🔧 After replacement, calibrate the pump in the service menu (for this, in the Mi Home application, go to Settings). → Additionally. → Sizing).

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If the pump is buzzing but not pumping water, try to scroll the impeller manually (like a screwdriver), often it "sticks" due to lime plaque, and after scrolling it starts working normally.

4.Problems with the electromagnetic valve

The electromagnetic valve is responsible for opening/closing the water supply from the tank. If it fails, the robot either doesn't supply water at all or it pours water continuously (worse!).

• 🔊 There is no characteristic click at the start of cleaning.
• 💧 Water drips even when the robot is off.
• 🚫 The application error Water valve error.

How to check the valve:

1. Remove the water tank and find the valve (usually located at the bottom of the tank).
2. Put the valve on voltage. 5V (You can use the power supply from the phone. The valve that's working must click and open.
3. If the valve does not respond, check the resistance of the winding with a multimeter (should be ~50-100 Oms).

Replacement of the valve will cost 800-1 500 ₽, But often the problem is solved by cleaning the contacts:

1. Remove the valve from the body (it is attached to 1-2 screws).
2. Wash it with an alcohol solution (do not use water!).
3. Clean the contacts with a stripe or small sandpaper.

⚠️ Note: Some models (e.g. DreameBot) W10) They have two valves, for water and for detergent, and if you use a non-original fluid, the second valve can clog more often.

5. firmware failures and software errors

Sometimes the problem is not the mechanics, but the firmware, which is especially true after updates or resets.

• 📱 Mi Home App Apps Show Error 5 or System Error.
• 🔄 Robot accidentally turns on/off water supply.
• 🔧 Wet cleaning settings are reset after rebooting.

How to fix it:

1. Reboot the robot: Hold the power button for 10 seconds, then turn it on again.
2. Reset the settings to factory: Settings → Additionally. → Resetting settings
3. Update the firmware through the Mi Home app (Software Update section).
4. Reconnect the robot to the application (sometimes helps with synchronization errors).

If the problem persists after the reset, try manually calibrating the water supply system:

1. Go to Settings. → Sizing → Calibration of water.
2. Follow the instructions on the screen (the robot will perform a test cycle of water supply).
3. If the calibration does not pass, contact Xiaomi with error logs.

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After resetting, be sure to reset the cleaning areas and water supply level. The robot can "forget" the previous settings!

Mechanical damage: cracks, wear of seals

If the robot fell or was subjected to severe vibrations, mechanical damage could occur:

• 💔 Cracks in the tank or tubes (water leaks without reaching the cloth).
• 🧰 Wear of sealing rubber bands (air enters the system and the pump does not create pressure).
• 🔧 Breakage of rag fasteners (water is supplied, but does not fall on the floor).

How to diagnose:

1. Pour water into the tank and leave the robot on a dry surface (for example, on a table). After 10-15 minutes, check if puddles have appeared.
2. Inspect the sealing gums on the tank and pump – they should be elastic, without cracks.
3. Check the rag mount: if it is broken, the water will drain past.

Repair of mechanical damage:

• 🔧 Cracks in the tank can be temporarily glued with epoxy glue (but it is better to replace the tank).
• 🛠️ Sealing gums are sold in remaplets (cost) ~300–500 ₽).
• 🧵 Broken rag mounts can be repaired with plastic glue or replaced with a holder (article for Mi Mop 2 Pro — XMSH03QM).

If the robot fell from a height, check:

• 📏 Body geometry – deformation can block water movement.
• 🔌 Sensor contacts (e.g., water level sensors).

7.When to contact the service: signs of serious breakdowns

If you've tried all of these methods, but the robot still doesn't supply water, it's probably a serious problem that you can't fix yourself.

• 🔥 On the control board, blackened elements or the smell of burning are visible.
• 💻 The robot does not turn on or respond to the application.
• 🔌 After replacing the pump or valve, the problem remained (possibly faulty control board).
• 📉 The water level in the tank falls on its own (leakage inside the enclosure).

Cost of repair in the service:

Before the trip to the service:

• 📋 Write down the robot model and serial number (located on the bottom).
• 📸 Take a picture of the errors in the app (if any).
• 🔄 Try resetting your settings – sometimes it saves time for diagnosis.

⚠️ Note: If the robot is warranty, do not disassemble it yourself - this will void warranty obligations).

FAQ: Frequent questions about water supply in Xiaomi robot vacuum cleaners