Have you ever opened the dishwasher after a cycle only to find unclean dishes? Or maybe there’s a puddle of gross water at the bottom that spills out (ew).
The likely culprit is a dirty dishwasher drain.
When you’re cleaning the dishwasher, don’t forget the drain! It plays a key role in keeping your plates, utensils, and glassware clean.
How to clean a dishwasher drain? The easiest way is with hot water, but you can also use a combo of baking soda and vinegar. A drain auger can remove any blockages.
Don’t let your dishwasher’s cleaning efforts go down the drain (ha!). Keep your kitchen free of dishwasher dish-water with proper maintenance.
Signs of Drain Clogging | How Often to Clean | How to Clean | After Cleaning | Unclogging the Drain | Clean the Drain Hose | Other Reasons for Poor Draining | Preventing Clogged Drains
Do Dishwasher Drains Need to Be Cleaned?
Yes! Your dishwasher does have a filter, but residue and debris can get past it, especially if it’s malfunctioning or broken.
That debris can then build up in the drain and hose, eventually leading to blockages – or worse, mould.
Common causes of a clogged dishwasher drain include:
- Large food particles
- Built-up grease and oil
- Broken pieces of dishes
- Soap scum or detergent residue
Regularly cleaning the dishwasher, filter, and drain ensures the appliance is hygienic, efficient, and functional. It can even extend your dishwasher’s lifespan!
Signs of a Clogged Dishwasher Drain
Even with routine cleaning, there are some signs that you should check your dishwasher drain ASAP!
- Slow drainage
- Unpleasant odours
- Pooling or standing water
- Dishwasher not cleaning dishes
- Odd noises (e.g. gurgling, popping)
- Food scraps and other debris left after a wash
How Often to Clean Your Dishwasher Drain
If you use the dishwasher frequently or wash lots of dirty dishes, you should clean the dishwasher drain once a month.
If you don’t use the dishwasher as often or pre-rinse your dishes, you can get away with cleaning the drain every 2-3 months.
Don’t want to get down and dirty with a drain? Book a professional kitchen cleaning and add the dishwasher to your service!
Before Cleaning the Drain
Before you start tackling the drain, practice safety first! Make sure your dishwasher is switched off and unplugged, or turn off the circuit breaker.
This will prevent accidental shocks and other safety hazards while you work.
Additionally, wear protective gear such as rubber gloves (and a face mask if you suspect mould).
To access the drain, you’ll need an empty dishwasher – so set aside all plates, utensils, and glasses.
Follow the instructions in your owner’s manual to take out each dish rack, then detach the bottom spray arm. Set them aside.
Locate the dishwasher filter (or drain filter) on the bottom – either under the spray arm or in a corner. Remove the filter and check if it needs cleaning.
You can soak it in some hot, soapy water while you tackle the drain, then scrub it clean.
If there’s any large food debris or other messes, clean the area with some paper towels so you can properly access the drain.
For pooled water, use a cup or ladle to empty it out. Soak up any excess water with kitchen towels or sponges.
How to Clean a Dishwasher Drain
Once you’ve accessed the drain and cleared out the area, it’s time to clean the drain itself!
And while you’re at it, clean the dishwasher filter to tackle two chores in one go.
Using hot water
This is the simplest dishwasher drain cleaner. It works best for routine cleaning or mildly dirty drains.
Boil a full kettle of water and let it cool to about 82ºC (180ºF) – typically the highest temperature of the rinse cycle. Pour hot water down the drain slowly, keeping an eye on the water level.
If you notice the water starting to back up, pause for a few moments and let it work its way through the drain and hose. The water should slowly melt away any debris or residue inside.
If the water doesn’t seem to be draining, though, that could be a sign of a larger clog that hot water itself can’t tackle.
Once the water has run out, wait 10-15 minutes so it makes its way through the drainage system. Then grab a soft brush (like a bottle brush) and some dishwasher detergent.
Scrub the filter housing and drain clean with detergent and water. Follow with some warm (not cold!) water down to rinse and check that everything is clear.
Using baking soda and vinegar
If you want a natural drain cleaner, try a combo of baking soda and white vinegar!
Pour 1/4 cup of baking soda into the drain, then follow with 1/2 cup of white vinegar. The fizzy reaction will loosen surface dirt and cut through mild build-up.
Let the baking soda solution sit for 10-15 minutes, then follow with some hot water (at most 82ºC) to flush out any residue.
You can also give the drain a quick scrub with a soft brush and some detergent, then rinse with hot water.
Watch to make sure everything drains out properly.
After Cleaning the Dishwasher Drain
If you’ve finished cleaning the dishwasher drain and found no issues (like a clog or break), it’s time to reassemble the different parts.
Put back the dishwasher’s filter, spray arms, and dish racks. Make sure everything’s locked in place.
Pour a cup of white vinegar into a dishwasher-safe container and place that on the top rack. Run a hot cycle with no detergent and no drying.
When the wash cycle is over, pop open the door a bit to let the dishwasher interior air dry. That should fully clean the drain and eliminate lingering odours.
How to Unclog a Dishwasher Drain
If you find a block in the dishwasher drain or the drain hose, cleaning won’t be enough.
Some signs of a clog can include water not draining properly or draining very slowly after cleaning.
You’ll need to remove whatever’s clogging your dishwasher’s drainage system.
Using a plunger
If the cleaning methods didn’t work, it’s time to bring out the big gun – a plunger.
(Just make sure it’s not the same one you use for your toilet. Yuck.)
Place the plunger so it fully covers the clogged drain. Apply firm but careful pressure as you plunge up and down for a few minutes.
That should dislodge any stubborn blockages in the drain. Follow with some hot water to flush out any debris and check the drainage.
Using a drain auger
Also called a drain snake or plumbing snake, a drain auger is a long, flexible metal cable with a spring or clamp at the end.
You push the auger into the drain (and even down into the drain hose) until it reaches the obstruction. The tip will snack the blockage, allowing you to retract the auger and remove the clog.
Wear rubber gloves and protective eyewear when using a drain auger. Layer some old towels on the floor under your dishwasher to catch any drips or water back-up.
When working the auger, be careful when retracting it to avoid any splashback. Do not pour anything other than water down the drain.
Wipe off any debris on the end of the auger once you’ve pulled it out. Repeat if necessary until the blockage is clear.
How to Clean the Dishwasher Drain Hose (Without Removing It)
The dishwasher drain hose carries away dirty water from your dishwasher to the sewer line or garbage disposal.
Access the hose and check for any obstructions or bends that could restrict water flow. Inspect the connection to the dishwasher and drainage system as well.
If you find a blockage, you can clean the drain hose without removing it by flushing the drain with hot water (up to 82ºC).
But if that doesn’t work – say, the water backs up – use the drain auger to remove debris and other obstructions. Be careful when working so you don’t nick the sides of the hose!
However, very stubborn clogs may require you to disconnect the hose from the dishwasher. Follow the instructions in the owner’s manual, and layer some old towels underneath to catch any spills.
Wipe the mouth of the hose and the connection with some paper towels, removing any grime you can reach. Then use the auger to reach for any blockages.
You can also flush out the hose by running some high-pressure water using a garden hose. Make sure to work outside!
Once the hose is clear, run a wash cycle to check that everything’s in working order.
Other Reasons Your Dishwasher Isn’t Draining Properly
If cleaning the drain and hose doesn’t solve your draining problems, you may need to check other parts of the dishwasher’s drainage system.
For those who live in areas that allow garbage disposal systems, you can try switching it on or checking for a jam. Any issues should be left to a professional to fix!
Drain trap
Depending on the installation, your dishwasher can connect to the drain trap or P-trap under the kitchen sink.
The dishwasher drain trap is part of your kitchen’s drainage system. It holds some water to prevent sewer gas and waste from going back up the pipes.
Grease, food scraps, and other gunk can build up in the pipes over time, including the drain trap. That eventually prevents the wastewater from draining out, and can even lead to a smelly dishwasher drain.
You can try to clean a dishwasher drain trap with hot water or a drain auger. However, it’s probably best to call a professional.
Drain pump
The drain pump helps flush out wastewater and debris from the drainage system. Check the manual for instructions on how to access the pump.
You’ll likely have to switch off the water line and pump, then disconnect the hose and water line. The pump will be located underneath the dishwasher.
Any sort of blockage in the drain pump will prevent it from flushing out the water and debris into the garbage disposal or sewer line.
If you’re not sure how to access the pump – or your dishwasher is built in – it’s best to contact a professional plumber. For rentals, contact your landlord or property manager so you don’t void your lease.
Tips to Prevent Clogs in a Dishwasher Drain
There are cleaning tips and steps you can take to prevent clogs and ensure your dishwasher drain continues working properly.
Scrape food debris from dishes before loading them into the dishwasher. You don’t have to pre-rinse, but removing large messes means less risk of something clogging the drain filter.
For dishwashers connected to the hot water tap or heater, run water for 30-60 seconds before starting a cleaning cycle.
Use the appropriate dishwasher detergent and the correct amount! This minimises the chance of detergent residue and soap scum building up in the filter, drain, or hose.
Regularly clean the dishwasher and components. This also lets you check for any issues – the sooner you catch them, the easier they are to fix.
Unclogged Mysteries – Dishwasher Drain FAQs
Got other questions or concerns about your dishwasher’s drain? Let’s unblock the answers.
How can I check if my dishwasher drain is clogged?
An easy way to check if your dishwasher drain is clogged is by running a quick or short cycle on an empty dishwasher.
If you see water pooling on the bottom of your dishwasher, that’s a sign of a clogged drain or filter.
Why is there standing water in the bottom of my dishwasher?
If there’s water pooled on the bottom of the dishwasher tub after a wash cycle, it’s likely due to drainage problems.
Common causes include:
- A faulty drain pump
- A dirty dishwasher filter
- A clogged dishwasher drain
- Bends or obstructions in the hose
Check every component, starting with the filter and drain. If you can’t identify a problem, contact your landlord or a professional plumber.
Is drain cleaner safe for a dishwasher?
It’s best not to use commercial drain cleaners on your dishwasher. These products aren’t usually formulated for dishwashers, and could damage the inside of the machine.
You’re also introducing unnecessary chemicals into your dishwasher.
How to clean mould from the dishwasher drain?
Clogged drains or filters can create the perfect environment for mould. You’re most likely to find mould in the dishwasher on the filter, drain, and any rubber parts.
It usually grows on food particles, grease, and detergent residue left lying in the drain for a few days.
Get rid of the mould by mixing vinegar and dish soap, then scrubbing the affected area with a stiff brush (like an old toothbrush). Wipe any residue away with paper towels.
Disinfect your dishwasher by running a hot cycle with a dishwasher-safe container of vinegar on the top rack.
Alternatively, spray the affected area with 3% hydrogen peroxide and let it sit for a few minutes before wiping it clean. Never mix hydrogen peroxide with vinegar.
What should I do if my dishwasher still doesn’t drain after cleaning?
If you’ve checked and cleaned everything – from the filter to the drain hose – it may be time to call a professional plumbing service.
The manufacturer might even have their own maintenance team who can check the dishwasher for you.
