Dirty water leaking from an FC7 can mean a full or mis-seated tank, incorrectly fitted hair filters or a damaged reservoir. Separate tank seating, liquid flow, suction and brush drive before ordering a part. Empty dirty water, keep electrical areas dry and run only the short test described for this exact model family. What the alert means: An overfilled tank or incomplete latch loses its seal during movement, while displaced hair filters can redirect water away from collection. What to distinguish first: Dry the outside, then locate whether leakage starts at the tank seam, latch or above the tank near the hair filters. 1. Confirm the exact symptom — An overfilled tank or incomplete latch loses its seal during movement, while displaced hair filters can redirect water away from collection. 2. Prepare safely — Switch off, unplug the charger and empty both tanks before removing a roller, filter or floorhead cover. 3. Apply the official check — Empty the dirty tank below its maximum mark, clean the sealing surfaces, refit both hair filters and lock the tank firmly. 4. Interpret one retest — Roll the machine briefly over a dry floor. If the empty undamaged-looking tank still leaks, stop and contact Kärcher. The official Kärcher procedure identifies this exact symptom and supports the checks above. Keep the charging port and motor vents dry, and never clear a blockage while the appliance can start. Stop for a damaged tank, battery heat, electrical smell, persistent leak or an error that returns after one clean test.
Models covered
Safety first
- Keep the charging port and motor vents dry, and never clear a blockage while the appliance can start.
What the symptom may indicate
Checks in the right order
- Confirm the exact symptom
An overfilled tank or incomplete latch loses its seal during movement, while displaced hair filters can redirect water away from collection.
- Prepare safely
Switch off, unplug the charger and empty both tanks before removing a roller, filter or floorhead cover.
- Apply the official check
Empty the dirty tank below its maximum mark, clean the sealing surfaces, refit both hair filters and lock the tank firmly.
- Interpret one retest
Roll the machine briefly over a dry floor. If the empty undamaged-looking tank still leaks, stop and contact Kärcher.
Stop and get qualified help when
- Stop for a damaged tank, battery heat, electrical smell, persistent leak or an error that returns after one clean test.
Next step
Repair, replace a part, or arrange a diagnosis?
Use the checks and stop conditions above to choose a cautious next step. A symptom alone never proves that the appliance has failed.
Resolve it without buying anything
Complete the 4 user-accessible checks in order. If normal operation returns and no warning sign remains, no replacement is indicated.
Replace only the confirmed part
If the checks isolate a worn or blocked component, match its complete reference to the exact appliance model before ordering.
This guide does not identify a replacement part. Do not order a generic component from the symptom alone.
Arrange a diagnosis before replacing the appliance
Stop at any warning sign listed above. A qualified diagnosis should confirm that repair is unsafe, unavailable or uneconomical before an appliance replacement is considered.
Sources used
- Kärcher — The official Kärcher procedure identifies this exact symptom and supports the checks above.
Last checked: 30 August 2026