Miele Dishwasher Not Draining: Causes, Diagnosis & Solutions

Is This an Emergency?

No, but don't ignore it. Standing water won't damage your dishwasher immediately, but:

• It will start to smell within 24-48 hours
• Mold can develop in warm, wet conditions
• Running another cycle could cause overflow

Do: Remove standing water manually with towels or a wet/dry vacuum.

Don't: Run another wash cycle hoping it resolves itself.

What Causes Drainage Problems?

In order of likelihood:

1. Blocked Filter (Most Common)

The filter at the bottom of your dishwasher catches food particles. When clogged, water can't drain.

Signs: Gradual worsening over several cycles, dirty residue on dishes.

2. Kinked or Blocked Drain Hose

The hose connecting your dishwasher to the garbage disposal or drain can become kinked, clogged, or frozen (if in unheated space).

Signs: Sudden drainage failure, gurgling sounds.

3. Garbage Disposal Knockout Plug

If your dishwasher is newly installed and drains to a disposal, the knockout plug may not have been removed.

Signs: Never drained properly since installation.

4. Drain Pump Failure

The pump that forces water out of the machine can fail, especially in units over 8-10 years old.

Signs: Humming sound without water movement, no drainage despite clear paths.

5. Control Board Issue

Rarely, the electronic control may not signal the pump to activate.

Signs: No pump sounds at all, possibly other functions affected.

What You Can Safely Check Yourself

Step 1: Clean the Filter

1. Remove the bottom rack
2. Locate the filter assembly (cylindrical, center-bottom)
3. Turn counterclockwise to remove
4. Rinse under running water
5. Clean the filter housing
6. Reinstall and test

Time: 5 minutes | Tools: None

Step 2: Inspect the Drain Hose

1. Pull dishwasher forward slightly (careful of water line)
2. Check hose for kinks
3. Disconnect at disposal/drain end
4. Check for blockages (use flashlight)
5. Reconnect securely

Time: 15 minutes | Tools: Pliers, bucket, towels

Step 3: Check the Air Gap (if equipped)

1. Locate air gap on counter (chrome cylinder near faucet)
2. Remove cap and inner cover
3. Clean any debris
4. Replace covers

Time: 5 minutes | Tools: None

Step 4: Run a Drain Cycle

After cleaning:

1. Close door firmly
2. Select "Drain" or run shortest cycle
3. Listen for pump activation
4. Check if water drains

What You Should NOT Do

When to Call a Professional

Call for service if:

• ✗ Filter is clean but water won't drain
• ✗ Pump makes no sound or only hums
• ✗ Error code F11 or F12 appears repeatedly
• ✗ Drain hose is clear but drainage fails
• ✗ You're uncomfortable with any DIY steps

Error Codes Related to Drainage

Repair Cost Expectations

If professional service is needed:

Preventing Future Drainage Issues

1. Scrape plates before loading (no need to pre-rinse)
2. Clean filter monthly — quick rinse under water
3. Run hot water at sink before starting dishwasher
4. Use quality detergent — cheap detergent leaves residue
5. Run garbage disposal before starting dishwasher

Next Steps

If DIY Fixed the Problem

Great! Add monthly filter cleaning to your routine to prevent recurrence.

If Problem Persists

1. Look up your error code for specific guidance
2. Schedule a service appointment for professional diagnosis
3. Note when the problem started and any changes you made

Standing water in your dishwasher is annoying but usually fixable. Most drainage issues are resolved with a simple filter cleaning — try that first before calling for service.