Code: F18🧺 Miele Dishwasher

Miele Dishwasher F18: Water Intake Valve Fault (Meaning, Causes, What to Do)

Reviewed 2026-10-26 · Based on 4 manufacturer & service sources

What the code means

Miele's support pages in the US and UK describe F18 as "Water intake valve faulty" (UK: "defective") and add: "This is a technical fault that you cannot remedy yourself." Miele's G 1 Series technical information manual explains the check behind it. It calls F18 the "flow meter stationary state monitor": the flow meter counts water coming in, and if it sends pulses while the electronics have not switched the inlet valve on, the control assumes the valve is open when it shouldn't be. The program is interrupted and the drain pump runs. The same manual says those unexpected pulses can also come from electrical interference inside the water diverter, so a stuck valve is the usual cause but not the only one. F18 is not the same as Miele's ordinary water intake fault (faucet off, blocked inlet filter or low pressure), which shows a separate message and is something you can fix yourself.

Likely causes

Safe DIY checks

⚠ Before you start

F18 can mean water is entering the machine without control. Keep the water supply off and the dishwasher switched off until it is repaired, and leave the electrical valve housing at the water connection closed.

  1. Let the drain pump finish, then switch the dishwasher off and turn off the faucet or shutoff valve that feeds it.
  2. Check whether water keeps trickling into the tub with the machine off. If it does, keep the water off until it is repaired, because a valve that sticks open can overfill or leak.
  3. Don't open the plastic housing at the water connection or dip it in water. Miele warns it contains an electrical valve.
  4. Note the model and serial number from the rating plate on the edge of the door.
  5. Book a repair with Miele Service (US 888-996-4353) or a Miele-experienced appliance technician.

🛠 When to call a pro

  • Any F18: Miele classes it as a technical fault for a technician. Per the technical manual, the technician checks that the inlet valve energizes during the fill step and de-energizes after it, and replaces the valve if water still enters once it is switched off.
  • The valve tests fine but F18 keeps returning: the technical manual says to check for interference from electrical parts in the water diverter and replace the diverter if needed.
  • The dishwasher is under warranty or extended cover: use Miele Service first.

Parts that commonly fix it

Always match the part number to your exact model.

⚙

Dishwasher water inlet valve

The usual repair for F18. Miele valves are model-specific (some sit in the WaterProof hose at the faucet), so match the part to your model number or let Miele Service fit it.

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⚙

Multimeter

For a technician's checks on the inlet valve and diverter wiring with the machine unplugged.

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Sources

  1. Miele USA support: The dishwasher display shows fault F18 (water intake valve faulty; technical fault you cannot remedy yourself; book a repair)
  2. Miele Great Britain support: Fault F18 (water intake valve defective)
  3. Miele G 1 Series Technical Information, section 3.18 Fault Code F18: Flow Meter Stationary State Monitor (program interrupted, drain pump runs; inlet valve open when not signalled; valve check; water diverter interference) via ManualsLib
  4. Miele USA support: Water inlet fault/Please open the faucet (the separate, user-fixable intake fault; warning about the electrical valve housing)

Last reviewed 2026-10-26. Always confirm against the manual for your exact model number.