Miele Dishwasher Not Draining? Here’s What to Do

Miele sells high-end dishwashers all over the world, from America to Europe to Australia. Miele appliances are known for being reliable and durable. But like with all dishwashers, drainage issues can sometimes occur.  

If your Miele dishwasher has a drainage problem, this article will outline what to do about it. We cover all of the most likely causes, along with the steps you should take to address them.

Why is my Miele dishwasher not draining?

Here are the most common problems that can cause a Miele dishwasher not to drain and how to fix them.

The filter is dirty

The dishwasher filter should be cleaned every month or two because neglecting this task can cause the filter to clog, leading to a Miele dishwasher that doesn’t drain properly.

If you haven’t cleaned the filter in a while, follow these steps to do so:

1. Remove the lower rack and locate the filter at the base of the tub.
2. Manually remove any water that hasn’t drained using a small container, turkey baster, or a sponge.
3. Turn the handle counterclockwise to unlock the filter, then lift it out. On some models, you may need to twist the base of the spray arm counterclockwise, remove it, and then lift out the filter underneath.
4. Carefully separate all of the parts of the filter. You may need to twist or pull them apart.
5. Rinse all of the filter’s parts under warm, running water. Use a soft brush and mild dish soap if they’re heavily soiled.

The non-return valve is clogged

The non-return valve is a small component located near the filter that prevents wastewater from flowing back into your Miele dishwasher during the draining process.

The non-return valve has a metal ball inside that must be able to move freely, otherwise drainage issues can occur. It’s not uncommon for food particles and debris to get inside the valve, clogging it up, and preventing it from functioning properly.

You can inspect and clean the non-return valve by following these steps:

1. Remove the lower rack.
2. Manually remove any undrained water.
3. Remove the lower spray arm and the filter.
4. Remove the non-return valve located in the filter housing by tilting its locking tab toward the base and then pulling it out.
5. Inspect whether the metal ball moves freely inside the valve or if it’s clogged by foreign objects.
6. If clogged, separate the non-return valve by pulling it apart gently. Then, rinse all of its parts, including the metal ball and rubber seal, under running water.
7. Once clean, reinstall the non-return valve in the dishwasher, ensuring it clicks into place.

The impeller is obstructed

The impeller is an important part of the drain pump. It’s a fan-like component that rotates, pushing water out of the dishwasher during the draining process. It’s powered by the drain pump motor.

It’s located directly beneath the non-return valve in a Miele dishwasher. If the impeller is obstructed by a foreign object, such as food debris, a piece of broken plastic or glass, or something else—which can often happen—the water won’t drain properly.

Here’s how to check the impeller:

1. Unplug the dishwasher.
2. Remove the lower rack.
3. Manually remove any water that hasn’t drained.
4. Remove the lower spray arm and the filter.
5. Remove the non-return valve.
6. Locate the impeller directly beneath where the non-return valve goes.
7. Inspect the impeller for any foreign items that may be obstructing it. Manually spin the impeller with your fingers to check all of its blades.
8. If the impeller is damaged, such as it having missing blades, the entire drain pump will need to be replaced.

The drain hose is kinked or clogged

The drain hose carries water from your dishwasher to your home’s drainage system, usually the garbage disposal or sink drain. If the drain hose is clogged or kinked, the water flow will be restricted, meaning your dishwasher won’t drain properly.

Follow these steps to check the drain hose:

1. Unplug the dishwasher and turn off its water supply.
2. Pull the dishwasher away from the wall.
3. Inspect the drain hose from the dishwasher to the sink drain or garbage disposal for kinks or blockages.
4. Straighten out any kinks.
5. If the drain hose appears clogged, disconnect it from the dishwasher and the disposal or sink drain. You may need to remove the dishwasher’s base or rear panel to access the drain hose connection.
6. Run warm water through the drain hose and use a plumber’s snake or a length of wire to clear any clogs.
7. Reinstall the drain hose and check whether it now drains properly.

The garbage disposal is blocked

If your Miele dishwasher is connected to a garbage disposal that’s clogged, it won’t drain. Fortunately, clearing clogs in the garbage disposal is usually straightforward. Simply run water in the sink above it for a few minutes while the disposal is running.

If that doesn’t work, try unplugging the garbage disposal, disconnecting the hoses attached to it, and checking them for clogs. At this time, you can also inspect the inlet ports where they connect to the disposal for blockages.

If you’ve recently installed the dishwasher or garbage disposal, the knockout plug in the opening where the dishwasher connects to the disposal may need to be removed. You can do this by disconnecting the dishwasher’s drain hose from the disposal and using a screwdriver and hammer to tap the plug out of the opening.

Consider hiring a professional

If you still haven’t been able to get your Miele dishwasher to drain despite following the tips above, or if you don’t feel confident handling these steps yourself, we recommend hiring a professional to inspect and repair your appliance.

Drainage issues are usually fixable and worth addressing. It’s not worth letting a high-end appliance like a Miele dishwasher sit unused simply due to a drainage issue.