Though there can be a number of reasons a dishwasher won’t drain, the issue can often be fixed with some quick troubleshooting steps. Learn what steps to take if your dishwasher won’t drain and tips to keep your dishwasher draining properly in the future.
What to do if your dishwasher won’t drain
Before troubleshooting the dishwasher, turn off the power to the machine by pulling out the fuse or switching off the circuit breaker in your home’s main power panel.
1. Check for a blockage
Make sure there’s nothing blocking the sump—located near the rear of the dishwasher—or the bottom part of the tub. If you find more than two to three cups of standing water, use a small container to remove as much of it as you can. You can unclog a dishwasher by checking for food particles, paper, or other debris and removing them.
Note that it’s normal for some dishwashers to have a small amount of water at the bottom of the tub after a complete cycle. Check your manufacturer’s manual to verify if this is normal.
2. Remove debris from the filter
Find the filter at the bottom of the dishwasher. It should be surrounding the base of the lower spray arm or at the back of the tub. Though most dishwashers have built-in grinders to process food particles and paper, debris can still clog the filter. Clear away any debris you find.
3. Assess the drain hose
The drain hose is a corrugated structure located right underneath the sink, between the drain pump and drain line. If you find any kinks in the drain hose, gently straighten them out.
To remove blockages within the drain hose, you may have to remove the hose from its current position. Loosen the clamps that hold the drain hose to the disposal. If there’s blockage, blow through one end of the hose to remove the debris.
4. Check the garbage disposal
Make sure the kitchen sink drain isn’t clogged. Remove the drain plug in your garbage disposal (a small plastic insert), and run the disposal to make sure the dishwasher drain isn’t clogged. Never put your hands down the garbage disposal—serious injury may occur.
5. Clean the air gap
The air gap is the small, chrome cylinder on the back edge of the kitchen sink. When you run the dishwasher, check to see if water comes out of the air gap. If this is the case, there’s a blockage between the air gap and the garbage disposer. Clear the blockage by removing the air gap cap and clean the inside of the air gap with a mixture of baking soda and water.
6. Make sure the dishwasher door latch is closed
If the door is unlatched, your dishwasher won’t drain completely. Latch the door and run a full cycle to see if the dishwasher drains. If you’re having trouble latching the door, you may need a latch replacement.
7. Check the drain valve
A drain valve opens the solenoid—an electromagnet found in the dishwasher—and allows water to drain during the wash cycle. To test the valve, push on the valve bracket to make sure it moves freely. Not all dishwashers have a drain valve, but if yours does and it seems to be frozen in place, you may need a drain valve replacement.
8. Test the motor
To test the motor, make sure the dishwasher is plugged in and getting power. Turn the dishwasher on and listen for a humming noise. If you hear a hum, the motor is receiving power but not turning. You’ll need a motor replacement if this is the case.
Dishwasher still not working?
If your dishwasher still won’t drain after troubleshooting these areas, hire a professional to assess the system. Newer dishwashers may still be covered by their limited manufacturer’s warranty. If that’s expired but your dishwasher is instead covered by a home warranty, your provider will send a trained service technician to access the problem. Along with a low monthly premium, you’ll only pay a service fee for the visit. To learn more about home warranties, read our reviews on the top home warranty providers or call Choice Home Warranty for a free quote.
Home warranties and dishwashers
Most home warranties will cover dishwasher repairs, and even replacements, depending on your specific plan. Providers like First American Home Warranty, Choice Home Warranty, and Select Home Warranty specifically provide coverage for dishwashers and other kitchen appliances like microwaves and garbage disposals. The repair or replacement process is as simple as contacting your provider and setting up an appointment with an approved contractor, who will come to your property to evaluate and fix the issue.
After the dishwasher repair technician inspects your dishwasher, they’ll let you know if a simple repair or complete replacement is necessary. If your dishwasher needs to be replaced, your provider should cover the entire cost of the replacement, minus the trade service fee.
All home warranty plans are different, so be sure to understand the terms and conditions before installing a replacement dishwasher.
If you don’t have a home warranty, read reviews on trusted, local service technicians and hire one to fix your dishwasher. Note that in this instance, you’ll have to front the out-of-pocket costs for a new dishwasher yourself. If you sign up for one of the best home warranty plans, you can save on future repairs. For example, the average dishwasher repair cost is $150. With our recommend provider CHW you would only pay a service fee of $75—that’s 50% savings.
Tips to keep your dishwasher draining properly
- Always turn on your garbage disposal prior to running the dishwasher to clean out food and debris in the system.
- Don’t use drain cleaner in the dishwasher. Chemical drain cleaners like Drain-O or Liquid Plumber should never be used because of their caustic ingredients that can damage rubber parts of the dishwasher.
- Make sure you’re using the right type of dishwashing detergent. Use only powder, liquid, tablet, or pod detergent specifically designed for automatic dishwashers.
- Check that you’re using the right amount of dishwasher detergent. Homes with soft water require about a quarter cup of detergent (too much detergent could cause permanent etching of glassware). Hard water areas require a full cup of detergent for a good wash.
- Perform annual maintenance on your dishwasher—this includes cleaning the filter and trap with a stiff brush and hot, soapy water, cleaning the spray arm holes with a stiff wire brush, checking the dish racks for cracks, checking the drain hose clamps to ensure they’re properly clamped, looking for leaks and cracks in the door seal, and making sure the pre-heating mechanism is functioning properly.
- If you think there’s an issue, address it quickly. Letting the problem sit can make the clog worse and may cause additional (more expensive) repairs. If the cost of a potential repair is holding you back, the cost of a home warranty may be more manageable. Warranty premiums are $25–$67 a month, and you only pay a nominal service fee any time you have a repair for a covered appliance.