How to tell if a dishwasher drain line is clogged?

Author: Perry Littel PhD  |  Last update: Tuesday, February 10, 2026

  1. Slow Drainage: If you notice your dishwasher or kitchen sink is draining slowly, there could be a clog forming, or even extensive buildup hiding in your kitchen's line. ...
  2. Gurgling Sounds: Have you heard loud gurgling coming from your dishwasher or kitchen sink?

How do I know if my dishwasher drain hose is clogged?

Signs Of A Clogged Dishwasher Drain Hose
  1. Odd Gurgling Sounds.
  2. Water Is Backed Up.
  3. Slow Drainage.
  4. Dishes Are Dirty.
  5. Standing Water.
  6. Preventing Dishwasher Clogs.
  7. First Class Plumbing With Art Plumbing, Air Conditioning & Electric.

How do you unblock a dishwasher drain pipe?

Clean the drain

Since it is common for debris to get stuck in the dishwasher drain, try cleaning it with a solution of equal parts baking soda and vinegar. Pour the baking soda and vinegar into the bottom of the dishwasher and let it sit for 15 minutes. Then run a rinse cycle at the highest heat setting.

How to clean a dishwasher drain hose without removing it?

Since it is common for debris to get stuck in the dishwasher drain, try cleaning it with a solution of equal parts baking soda and vinegar. Pour the baking soda and vinegar into the bottom of the dishwasher and let it sit for 15 minutes. Then run a rinse cycle at the highest heat setting.

Should there be standing water in a dishwasher drain hose?

Yes, it's normal. The drain pump would get as much water out of the sump as it can, but when the cycle is completed there will be an amount of water still in the drain hose.

How To Fix a Dishwasher That Won't Drain

How do I get rid of standing water in the bottom of my dishwasher?

Remove Any Standing Water

Empty your dishwasher for a full, unobstructed view. Take out the bottom rack. Remove the excess water with a cup or soak it up with towels or a turkey baster and sponge. You can also use or a wet/dry shop vac to suction it all out.

Can I snake my dishwasher drain hose?

You can use one of those inexpensive, snake-like tools or a commercial de-clogger.

Why is my dishwasher not draining but no blockage?

Reasons why your dishwasher might not be draining

We recommend checking the filter first, because that's quite easy to solve yourself. If the filter isn't blocked, the other potential reasons are: A blockage in the dishwasher's drain hose. Debris in the dishwasher's drain pump.

How should dishwasher drain hose run?

The high loop helps prevent the excess dirty water in the drain from flowing back into the dishwasher particularly on a long run like yours. By running it high, it will be one less obstruction inside the cabinet under the sink. It will come high into the cabinet and dive directly into the garbage disposer.

How long do dishwashers last?

Average Lifespan of Dishwashers

According to reputed appliance repair technicians and manufacturers, the average home dishwasher lasts between 10 to 15 years with regular use and proper maintenance. Even an appliance from the best dishwasher brands will only last 15 to 20 years at most.

How do you unclog a drain line?

A straightforward yet effective approach to addressing a clogged drain pipe involves simply using hot water mixed with dish soap. This method, ideal for tackling minor blockages, leverages the degreasing power of dish soap combined with the force of hot water to dislodge and dissolve clog-causing residue.

How do I force my dishwasher to drain?

Press and hold the cancel button for at least three seconds—or the amount indicated—to activate the draining mechanism. Once the drainage sound completes, and your dishwasher shuts off, check the inside of the unit for standing water.

How to unblock a dishwasher drain pipe?

Unblock a dishwasher with bicarb

You can dissolve food and grease residues with bicarbonate soda. Sprinkle the soda in the blocked drain of the dishwasher. Pour a litre of hot boiling water and leave the bicarb to work for 30 minutes. Rinse with hot water and check that the dishwasher drains again.

How do I test my dishwasher drain?

To do this, set your multimeter to 200 ohms. Then place the two multimeter probes onto the drain pump's tabs from which you removed the electrical connections. If your drain pump is working properly, the multimeter should show a reading of between 160 and 260.

How do I know if my drain hose is clogged?

If there is standing water in the washer tub following the final spin cycle, or there is water leaking from the bottom of the washer cabinet, the washer's drain pump or drain hose could be clogged or broken and preventing the water from being emptied from the appliance into a laundry tub or standpipe.

How do I know if my dishwasher drain pump is clogged?

About five seconds after you start running a dishwasher cycle, the drain pump will start making a low humming noise. This will be due to a piece of glass blocking the impeller from turning, resulting in the dishwasher pump not working properly. When this happens, you'll need to remove the blockage.

What happens if dishwasher drain is clogged?

A clogged or overflowing dishwasher can cause extensive water damage to your home if left untreated. If you have a dishwasher that isn't draining, the first step is to check for an obstruction in the drain hose. If this is clear and there is still no drainage, it may be time to call a plumber.

How do you unclog a dishwasher with standing water?

Try vinegar and baking soda

Mix together about one cup each of baking soda and vinegar and pour the mixture into the standing water at the bottom of the dishwasher. Leave for about 20 minutes. If the water is draining or starting to drain at that time, rinse with hot water and then run the dishwasher's rinse cycle.

Should water remain in dishwasher drain hose?

Is your dishwasher not draining properly? While it's normal for there to be a bit of standing water at the bottom of your dishwasher from time to time, if you're seeing an inch or more, it's highly possible you have a clogged dishwasher.

How do I know if my dishwasher filter is clogged?

Signs you should be cleaning your filter more

Visible build-up of food in the filter. Water not draining properly. Nasty and unpleasant odours.

Can you use drano in a clogged dishwasher?

Let's get right to the point: Drano should never be used in a dishwasher because the harsh chemicals in Drano will damage the plastic parts of the appliance and could leave toxic residue on your dishes. If you are looking for an effective way to unclog your dishwasher drain or spray arms, this article will help.

Why is the water not draining from my dishwasher?

There are a few reasons why your dishwasher won't drain. The most common source of clogs comes from a blockage in the dishwasher's filter. Or, you may have an issue with your dishwasher's air gap, drain valve, drain hose or even your garbage disposal, causing your dishwasher to clog.

Does a 10 year old dishwasher have a filter?

If your dishwasher is over 10 years old, it probably has something called a self-cleaning filter.

Do all dishwashers have a food trap?

All dishwashers have a filter, however not all of them require regular maintenance. The location, type and instructions about how to keep the dishwasher clean may vary depending on the make and model of the appliance. Be sure to consult your product manual before removing and cleaning the filter.

Previous article
What PSI is too high?
Next article
Does homeowners insurance cover Roto Rooter?