Miele Dishwasher Error Code F70 — Waterproof System Activated (Flood Protection)
What this means
Error F70 is Miele's Waterproof system alert — water has accumulated in the base pan of the dishwasher, activating the float switch. This is a critical safety feature that shuts down the dishwasher and activates the drain pump continuously to prevent flooding. Causes include a leaking door seal, cracked sump, loose hose clamp, failed circulation pump seal, or a leaking inlet valve. This error should be addressed immediately.
Alternate codes: F 70
Step-by-step fix
4 stepsTurn off water and power immediately
Shut off the water supply tap and turn off the dishwasher at the circuit breaker. Place towels around the base to catch any escaping water.
The drain pump may be running continuously — this is by design to pump out the leaked water. Let it run until the water is drained.
Remove the base plate and check for water
With power off, carefully slide the dishwasher out from the cabinet. Remove the bottom base plate (usually 2–4 screws). Use towels to mop up any water in the base pan. Note how much water there is and where it appears to be coming from.
Tilt the dishwasher slightly backward to pool the water at the back where it is easier to access.
Identify the leak source
Inspect all water connections: inlet hose, drain hose, sump seal, circulation pump connections, door seal gasket, and spray arm connections. Look for drips, wet spots, or mineral deposits (white crusty residue) that indicate a slow leak over time.
Place dry paper towels under each connection, run a short cycle, and check which towel gets wet first to isolate the leak.
Reset the float switch and test
After drying the base pan completely, press down the float switch (a small styrofoam block in the base) to reset it. Reassemble and run a test cycle while watching for new leaks.
If the float switch is stuck in the up position due to calcium deposits, gently clean it and ensure it moves freely.
When to call a professional
If you cannot identify the leak source, or if the leak is from the circulation pump seal or sump housing, a technician should perform the repair to ensure watertight reassembly.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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