In most homes, a dishwasher is an important appliance that is hard to live without. When it stops working properly, it can cause major inconvenience. In this guide, we will explore the most likely reasons that your KitchenAid dishwasher has stopped draining, and give you actionable advice on what you can do to fix it yourself.
Why Your KitchenAid Dishwasher is Not Draining
If a KitchenAid dishwasher is not draining there are only a handful of possible causes, making it relatively simple to troubleshoot. In this part of the guide, you will discover what each of the causes are, with a short explanation of how they affect the way your dishwasher drains.
Clogged Water Filter
Your KitchenAid dishwasher contains a water filter that is designed to catch large pieces of debris, preventing the drainage system from becoming clogged. If the filter becomes loaded with this debris, grease or other material, it will block the flow of wastewater preventing the dishwasher from draining.
Drain Hose Kinked or Obstructed
The drain hose connects from the appliance drain pump to the sink or garbage disposal drain providing a clear passage for dirty water to flow out of the machine. If this hose becomes blocked, kinked or obstructed it prevents the water from draining out of the bottom of the dishwasher, resulting in standing water.
Any form of damage or kink that occurs within the hose typically happens during installation. Whereas clogs are usually the result of grease or scum build-up gathering in the lowest point of the hose pipe.
Blocked Air Gap
A dishwasher air gap is a cylindrical-shaped fitting that connects the appliance to your sink’s drain. The air gap’s job is to prevent dirty water from flowing back into the appliance during the draining cycle and to keep clean water from flowing back out of the dishwasher during the wash cycle. Sometimes, the air gap can become caked with debris and become stuck closed, not allowing water to drain when it should.
Component Failure
Finally, several components work together to draw waste water out of the appliance and clear it through the waste pipe. If any one of the components malfunctions, the appliance simply won’t drain properly. The most common parts that can fail and affect a KitchenAid dishwasher’s drain process include the drain pump and the drain solenoid valve, both of which we will talk about in more detail later.
Fixing A KitchenAid Dishwasher That Won’t Drain
As with all of our troubleshooting guides, the aim is to start with the potential problems that are easiest to diagnose and the simplest to fix. So let’s start by inspecting the water filter.
1. Inspect the Filter For Clogs
The water filter will be located in the base of the dishwasher underneath the lower dishrack.
- Take the bottom rack out of the dishwasher.
- Locate the cylinder-shaped filter housing at the bottom of the tub. Turn it counterclockwise to undo it, and pull it out.
- You will find two filters in one housing, a coarse filter to catch large objects and a fine mesh filter that is designed to collect smaller food particles. Wash both of them in hot soapy water, using a soft-bristled scrub brush to remove any stubborn buildup of scum or grease.
- Replace the filter unit back into its housing, and turn the clockwise to lock it into place.
- Return the dishrack where it belongs.
2. Check The Drain Hose
If cleaning the filter does not fix your drainage issues, next inspect the drain hose, for damage, kinks or clogging.
- Disconnect the power from the appliance and turn off its water supply.
- Using a screwdriver, remove the front panel at the bottom front of the dishwasher to access the drain pump and drain hose.
- Disconnect the drain hose from the drain pump and inspect it for blockages. You may need to remove the other end of the hose as well, which is connected to the garbage disposal or air gap under the sink.
- Use a long straight piece of wire and push it through the hose section to remove any trapped grease or scum inside. I recommend bending the end of the hose to create a hairpin to avoid the sharp end of the wire from piercing the hose.
- Flush the drain hose to check that water runs freely through it and replace it. If you cannot clear the hose I would recommend replacing it with a low-cost universal drain hose available here.
- Put the front kick panel back on and turn the water and power back on to test the appliance. If it still does not drain properly, move on to the next troubleshooting steps.
3. Inspect The Air Gap and Garbage Disposal
Sometimes the air gap or garbage disposal the dishwasher is connected to can become clogged. If the filter and hose are clear, conduct these steps.
If your dishwasher is connected to an air gap, try cleaning it out.
- Remove the air gap cover.
- Use a small scrub brush, toothbrush or a piece of paper towel to remove any visible debris, hair or scum.
- Replace the air gap cover.
If your KitchenAid dishwasher is connected to the garbage disposal:
- Make it a point to run the disposal for a few seconds before running the dishwasher. This will help get rid of any debris that may cause a blockage when the dishwasher drains.
4. Clean out the Sump Area
The bottom of the dishwasher tub is called the sump area. Food and foreign objects will often come to rest here causing draining problems. Follow these simple steps to clear the sump area:
- Disconnect the power to the appliance.
- Use a shop vac, old towel or sponge to remove as much water as possible from the tub.
- Remove the mesh and plastic water filters that cover the lowest point of the dishwasher sump.
- Remove any chunks of food or foreign debris like broken glass that you find there.
- Inspect the drain pump impeller to see if it spins freely. You may need to use a thin tool to spin the impeller such as a screwdriver or a blunt knife
- If the Impeller is not moving free, use an old toothbrush to scrub it with dish soap until it spins freely.
- Replace all the parts you removed and test if the dishwasher drains.
4. Inspect the Check Valve
Not all dishwashers have check valves, but most do. The check valve opens and closes during the drain cycle to keep water from flowing back into the dishwasher. You should inspect the check valve to make sure it can open and close easily by following the steps below.
- Start by making sure the dishwasher is completely turned off and disconnected from the power source. This is important for your safety during the inspection.
- Locate the check valve, which is typically located on the inside of the dishwasher, near the drain hose or drain pump. Consult your dishwasher’s user manual if you’re unsure about its exact location.
- Take a close look at the check valve for any visible signs of damage or blockage. Check for cracks, debris, or any foreign objects that might be obstructing the valve’s proper functioning.
- Depending on the design of your dishwasher, you may be able to manually operate the check valve to test its functionality. Gently move or lift the valve to see if it opens and closes smoothly. A working check valve should move freely and close tightly.
- If the check valve appears to be in good condition, you can test it further by running water through the dishwasher. Connect the dishwasher to the water supply and turn it on briefly. Pay attention to the water flow during the draining process. If the check valve is functioning correctly, water should flow out smoothly and there should be no backflow.
Professional assistance: If you notice any signs of damage or the check valve is not working properly, it’s recommended to seek professional assistance. A qualified technician will be able to diagnose the issue accurately and provide the necessary repairs or replacements.
6. Drain Pump Malfunction
The drain pump is the main component responsible for the removal of water from your KitchenAid dishwasher. If it malfunctions, water will not be able to flow out of the appliance. To check this important part, follow the steps below.
- To diagnose a possible issue with the drain pump in your KitchenAid dishwasher, follow these steps:
- Turn off and disconnect the dishwasher for safety.
- Remove the kick plate to access the drain pump located at the bottom.
- Inspect for obstructions and remove any debris clogging the pump or drain hose. Ensure the pump impeller spins freely.
- Use a multimeter to test pump continuity by checking resistance between pump motor terminals. Lack of continuity indicates a faulty motor.
- Check for the power supply by reconnecting the wires and running a drain cycle while measuring the voltage at the pump connections with a multimeter. Low or no voltage may indicate control board or wiring issues.
Here’s a visual guide on how to replace the KitchenAid dishwasher pump
If unsure or unable to diagnose, it’s recommended to contact a professional technician for assistance in accurately identifying and resolving the problem. Always prioritize safety and refer to the user manual for specific instructions.
7. Check the Drain Solenoid Valve
Many KitchenAid dishwashers include a drain solenoid valve that opens and closes to allow water to exit the appliance. If this part fails, water cannot leave the dishwasher. To check that the drain solenoid valve is functioning properly, follow these steps.
- Turn off and disconnect the dishwasher for safety.
- Locate the drain solenoid valve, typically found near the drain pump or in the control panel.
- Inspect the valve for any visible signs of damage or blockage.
- Use a multimeter to test the solenoid valve for continuity. Disconnect the wires and place the multimeter probes on the valve terminals. A lack of continuity indicates a faulty valve.
- If the solenoid valve appears damaged or fails the continuity test, it may need to be replaced. Consult a professional technician for further assistance or replacement.
You may also like to read Dishwasher Stuck On Drain Cycle, Even When Empty
When To Call An Appliance Technician
Even though I mentioned at the beginning of this post that most of these fixes can be done by most DIYers, if you are ever uncomfortable with making these repairs yourself or don’t feel you have the expertise needed to complete them correctly, do not hesitate to schedule an appointment with a licensed professional.
While most of the steps in this article require simple cleaning, if your dishwasher is not draining due to a malfunctioning component, an experienced technician will be able to spot the problem right away and get it fixed for you quickly and trouble-free.
Andy has over 8 years of experience working on residential household appliances, performing diagnostics, and repairs across most major brands. He graduated from the Denver Institute of Technology, is NASTeC certified, and has worked for Mr. Appliance. Andy has contributed to features on major publications including Better Home & Gardens, Family Handyman, and Yahoo.com.