Miele Washer F18 Error — Aquastop Fix

What it means

Miele F18 error means the Aquastop flood protection sensor in the base of the machine has triggered — water has leaked into the base tray.
Switch off and unplug the machine immediately and call a Miele-authorised technician.

Affected Models

Miele W Series Front Load Washer
Miele WDD Series Washer
Miele WCR Series Washer
Miele TwinDos Washer
Miele PowerWash Washer

Common Causes

Leaking drum seal or door gasket allowing water into the base
Cracked or disconnected internal hose
Sump pump seal failure causing a slow internal drip
Overfilling due to a faulty inlet valve — water overflows into the base
Aquastop float stuck in the triggered position after a minor spill

How to Fix It

Switch off and unplug immediately.

F18 means water is present in the machine base.
Switching off and unplugging is essential before any inspection.
Do not restart the machine until the leak source has been found and fixed.
Tilt the machine to drain the base tray.

With the machine unplugged, carefully tilt the machine forward by about 30 degrees and hold for 1–2 minutes to drain water from the base tray.
Have towels ready on the floor.
This clears the Aquastop float so the error can be reset, but does not fix the underlying leak.
Inspect the door gasket and external hoses.

Check the door seal for tears and all visible hose connections at the back of the machine for looseness or cracks.
If you can identify a minor visible fault such as a loose hose connection, tighten it — but still have a technician confirm no other leaks before running a full wash.
Book a Miele technician.

F18 caused by an internal leak requires professional repair.
Miele technicians carry the correct seals and parts for all Miele models.
Attempting to repair internal seals without Miele experience risks further water damage.

When to Call a Professional

F18 almost always requires a Miele-authorised technician.
The source of the leak must be found and repaired before the machine is used again.
Do not restart the machine with water in the base.

Frequently Asked Questions

Miele F18 appeared once but the machine seems dry — is it safe to restart?

A single F18 that appeared briefly may have been triggered by a minor spill or a stuck float. Tilt the machine to drain the base, allow it to dry for 24 hours, then restart and monitor closely for the first cycle. If F18 appears again, there is an active internal leak that needs a technician.

Can I prevent Miele F18 from happening again?

Regular maintenance helps: check the door seal for tears every 6 months, do not overload the machine (which stresses the drum seal), and run Miele-approved descaler or drum cleaning cycles as recommended. However, F18 can also occur due to normal component wear — it is not always preventable.