Xiaomi vacuum cleaner stopped doing wet cleaning: diagnosis and repair

Your Xiaomi Mi Robot Vacuum or Viomi suddenly refused to wash floors, although before coping with wet cleaning by “excellent”? The problem is found in models with a wash function – from the budget Mi Mop 2 Pro to the flagship Xiaomi Robot Vacuum X10+. In 80% of cases, the malfunction is not due to a breakdown, but to banal operating errors or software failures. In this article, we will analyze all possible causes – from a clogged tank to a damaged pump – and also give step-by-step instructions for diagnosis and repair.

First, determine how the problem manifests itself:

• 🚫 The vacuum cleaner doesn’t spray water – the tank is full, but the floor remains dry;
• 💧 Water drips, but does not wash - the liquid leaks out, but the brush does not rotate;
• ⚠️ Screen/app error – fault code (e.g. Error 12 or Water tank error);
• 🔄 The wash function is turned on, but immediately switched off.

If the vacuum cleaner stopped wetting the cloth after falling or hitting it, the pump or the tubes are probably damaged, you can't do without disassembling it, but if the problem comes after updating the firmware or replacing the water, it's the software or the clog, let's start simple.

1. Check of water tank and supply system

The most common reason is the wrong installation or clogging of the tank. Even if you "did everything as usual", check:

• 🔍 The tank cover is closed before clicking - if it fits loosely, the sensor blocks the water supply;
• 💦 Water is flooded to the mark MAX — Too full or empty tank can be triggered as a mistake;
• 🧼 Use distilled or filtered water – hard water from the tap leaves a plaque on the pump;
• 🚫 No foreign objects – hair, thread, or debris can block the valve.

How to check:

1. Remove the tank, wash it with warm water (no detergents!).
2. Blow the hole for water supply (you can use a can of compressed air).
3. Install the tank back and listen - when you turn on the sink, the sound of the pump running (light buzzing) should be heard.

Once a week.|Once a month|Only when the smell comes|Never cleaned.-->

⚠️ Warning: If the tank has water for a week or more, it may have formed a fungus or mold inside, in which case, wash it with a solution of vinegar (1:1 with water) and dry it for 24 hours.

2. Closure or damage to tubes and valves

Xiaomi vacuum cleaners' water supply system consists of thin silicone tubes and an electromagnetic valve, which eventually clog up:

• 🧵 Hair and threads - wound on the valve;
• 🧂 Lime raid - if you use tap water;
• 🛑 Dust and dirt - fall due to a loosely closed tank lid.

How to clean:

1. Unplug the tank and find a tube going from it to the vacuum cleaner body.
2. Take the phone off carefully (a flat screwdriver may be required).
3. Wash it under running water, if necessary, clean with wire (diameter not more than 1 mm!).
4. Check the electromagnetic valve (located next to the pump) - it should click when the wash is turned on.

If the water is still not flowing after cleaning, the tube may be clamped or torn. Examine it along the entire length, especially in the places of bends. For Xiaomi Mi Mop 2 and Viomi V3 models, it will cost 300-500 rubles to replace the tube (the original part is ZNMS18WM).

3. Failure of the pump or electronics

If the tank and the tubes are clean, but the water is not supplied, the problem is the pump or the control board.

• 🔇 No sound of a pump working;
• 💡 Error 12 (failure of the washing system) is on the screen);
• 🔌 The vacuum cleaner is turned on, but the washing function is not activated.

How to diagnose:

1. Remove the bottom cover of the vacuum cleaner (a cross screwdriver will be required).
2. Find a pump – it looks like a small cylinder with wires.
3. Check the contacts on the board - whether there is oxidation or breaks.
4. Connect the vacuum cleaner to the charger and turn on the wash. If the pump is not vibrating, it's burned.

⚠️ Warning: If the pump is buzzing but not pumping water, don't try to disassemble it - 90% of the time it will cause permanent failure.

4. Firmware failures and software errors

After updating the firmware or resetting the settings, the vacuum cleaner may "forget" how to work with the wash function.

• 📱 In the Mi Home app, the washing function is inactive;
• ⚙️ The vacuum cleaner screen flashes a water icon, but cleaning doesn't start;
• 🔄 The vacuum cleaner turns on the wash for 2-3 seconds and turns it off.

How to fix it:

1. Reset the vacuum cleaner: Hold the power button for 10 seconds.
2. Update your firmware through the Mi Home app: Device profile → Settings → Update your firmware
3. If the update does not help, reset: Settings → Additional → Reset to factory

Save cleaning cards (if any)| Record power settings|Untie the vacuum cleaner from your Mi Account (if you plan to sell)|Connect to charging-->

For Xiaomi Robot Vacuum S7 and later after reset, it may be necessary to recalibrate the sensors.

1. Place the vacuum cleaner on a flat surface.
2. In the app, select Settings → Calibration.
3. Wait for the process to be completed (it will take 1-2 minutes).

5. Problems with the rag and the detergent module

Sometimes the vacuum cleaner pumps water, but the floor doesn't clean -- it's the rag or the washing module.

• 🧺 The rag is properly installed - should fit snugly to the base;
• 🔄 The washing module is not locked - some models (for example, Viomi) V2) have a physical switch;
• 🧼 The cloth is not worn out - if the fibers are worn off, the water just drains past;
• 🚫 No foreign objects – coins or pebbles can block the spin.

How to fix:

1. Remove the washing module (usually mounted on latches).
2. Wash it under water, remove hair and debris.
3. Check the bearing of rotation - it should spin without jamming.
4. If the cloth is torn, replace it (original for Xiaomi cost 200-400 rubles).

💡

Use two rags: one for wet cleaning, the other for dry cleaning. This will extend the life of the detergent module by 2 times.

6 Mechanical damage after falling

If the vacuum cleaner fell from a height or hit the furniture, could be affected:

• 🔧 Fixing of the detergent module - cracks in the plastic;
• 💧 Water supply tubes - inflections or breaks;
• ⚡ Management fees - contact withdrawals.

How to diagnose:

1. Check the body for cracks.
2. Check if the washing module is in the back.
3. If the vacuum cleaner is turned on, but the washing does not work, most likely, the board is damaged (diagnosis is needed in the service).

⚠️ Warning: After falling, do not try to turn on the vacuum cleaner if you hear the smell of burning or see melted parts!

7. When do you contact the service?

If you've tried everything, but the vacuum cleaner still doesn't wash, it's time to carry it for repair.

• 🔥 The board shows burnt-out elements;
• 💦 The pump does not respond to commands (no sound, vibration);
• ⚡ An unknown error is on the screen (e.g. Error 24);
• 🛠️ Replacement of tubes or valves (unless you are confident in your abilities).

Average cost of repair:

💡

Before visiting the service, drop the vacuum cleaner to the factory settings and remove it from the Mi Home account - this will speed up the diagnosis.

FAQ: Frequent questions about wet cleaning in Xiaomi vacuum cleaners