Portable Dishwasher Not Draining? Easy Fixes to Try

On this page (7 sections)

1. What to check first when a portable dishwasher is not draining
2. How can you tell a sink clog from a dishwasher problem?
3. Why does a portable dishwasher stop draining after you move it?
4. Can a drain hose extension help a short hose?
5. Replacement hoses and cleaners for a slow drain
6. When should you call the maker or a repair pro?
7. Which fix to try first for a portable dishwasher not draining

If your portable dishwasher is not draining, the cause is often simple and quick to check. Start with the drain hose, then the sink and the filter, and rule out each one before you spend money on parts.

Our countertop and portable dishwashers guide compares the tank, faucet-fed and 18-inch portable types. This page stays with drain problems and the checks that come before a repair call.

What to check first when a portable dishwasher is not draining

Unplug the unit, then check the drain hose, the sink and the filter, in that order. These three checks cover the simple causes, so start there before you try anything else.

Unplug the unit before any check

Unplug the dishwasher before you touch the hose, the filter or any part inside.

If the unit has just run a hot cycle, let it cool first. Keep a towel nearby, since a little water often spills when you disconnect a hose.

The Consumer Product Safety Commission publishes general appliance safety information, which is a good place to start if you are unsure.

Portable dishwasher not draining because of a kinked hose

A kinked or pinched drain hose is easy to miss. Follow the hose from the unit to the sink and look for a sharp bend, a spot pinched behind a cabinet edge or a section that has been crushed.

Straighten the hose, then run a short cycle to see whether the water leaves. If the hose still bends sharply at one spot, move it so it lies in a gentle curve.

Check both ends too. A hose that has slipped off a connection can leak, so push each end on firmly and secure it as the manual says.

Check how high and how long the hose runs

Your maker's manual sets a height and length limit for the drain hose. A hose set above that height, or one that runs too long, may keep water from leaving the unit.

Measure from the floor to the highest point of the hose. Compare that number with the limit in the manual, and lower the hose if it sits above the limit.

Ask the maker before you change the hose length, since the limits depend on your model. Compare any extension's length with the limit in the manual, not with the distance you hope to cover.

Clear the sink drain and check the filter

Some drain problems start in the sink, not in the unit. Run the kitchen sink on its own with the dishwasher off, and watch for slow draining or water backing up.

If the sink drains slowly even without the dishwasher, the clog is in the sink drain. That is a plumbing problem, so call a plumber if it keeps coming back or the pipes need to come apart.

Next, clean the dishwasher filter as the manual says, since food and grease in the filter can slow the flow. Then check that the unit sits level, because a tilted unit may not drain as it should.

How can you tell a sink clog from a dishwasher problem?

If the sink backs up when the dishwasher is off, the problem is the sink, not the unit. If the sink is clear and water stays in the dishwasher tub, the problem is in the unit, its hose or its filter.

Water left in the tub after a full cycle points to the hose, the height or the filter. A clear tub with a backed-up sink points to the sink drain.

Many dishwashers use a pump to push water out at the end of a cycle. A blocked hose or a clogged filter can leave that water behind in the tub.

Look up any error code in your manual, since each maker uses its own codes. SPT, for one, says its 18-inch portable shows fault codes on an error alarm.

If the code is not in the manual, contact the maker before you take the unit apart.

Why does a portable dishwasher stop draining after you move it?

Moving the unit can pinch or kink the drain hose, or shift the hose end in the sink. Roll the unit slowly, watch the hose as it goes and check it before you start a cycle.

Portable models roll out for use and roll back for storage, so the hose gets moved often. A hose that sat fine last week can sit differently today.

Tank models drain through a hose too, so the same hose checks apply to them.

Can a drain hose extension help a short hose?

A drain hose extension can add reach when the hose falls short of the sink, but a longer run can make draining harder. Add only the length your manual allows.

Extension kits with an adapter, clamps and a hose holder

Both kits here include an extension adapter, two clamps and a U-shaped hose holder. Each comes with connection heads in 3/4, 7/8, 1-1/4 and 1-1/2 inch sizes.

The Anchira kit is 3.2 feet long, so it suits a short extra run. HLMOptimo is the longer of the two kits, so check the length on the package against your measurement.

Both kits are sold for washing machines and dishwashers alike. Match the connection size to your unit's drain outlet, and confirm that your manual allows an extension.

To measure, run a tape from the unit's drain outlet to the sink drain, then allow for the bends the hose has to make. Write the number down before you shop.

Before you change the drain for good, read can you install a portable dishwasher permanently. Permanent drain changes belong to a licensed plumber.

Replacement hoses and cleaners for a slow drain

A new hose can replace one that is cracked or permanently kinked, and a cleaner can help with buildup in the spray arms, filter and pipes. Neither one clears a clogged sink, so run the sink check first.

Replace a hose that is cracked, leaks at a joint or stays kinked after you straighten it. For more options, see best portable dishwasher hoses and extension kits.

Eight-foot corrugated hose with an elbow end

Eastman gives this 8-foot hose a 90-degree rubber elbow end, which it says fits tight spaces with ease. The universal end fits 5/8 inch, 7/8 inch or 1 inch drain outlets, so measure your outlet before you order.

Eastman says the corrugated PVC resists kinking and crimping. The hose carries a 1-year limited warranty.

Eastman sells it for connecting a dishwasher to an air gap, a garbage disposal or a drain tailpiece. It suits a replacement only when your unit's outlet size matches and your manual allows a swap.

A cleaner for spray arms, filter and pipes

Finish's dishwasher cleaner liquid is made for buildup, not for a clogged drain. Finish says it targets hidden grease, hard water buildup and limescale in the spray arms, filter and pipes.

Finish directs you to empty the dishwasher, stand the bottle upside down in the bottom rack and run a hot cycle. It says the cleaner works with standard, older and small dishwashers.

Check your manual before you run it in a small unit, and make sure the bottle fits the rack.

A cleaner will not clear a kink or a clogged sink, so keep the hose and sink checks first.

The wrong soap can cause trouble too. COMFEE' says regular liquid dish soap will cause dishwasher problems, so check which detergent your manual names, and see our detergent guide for the forms.

When should you call the maker or a repair pro?

Call the maker or a repair pro if the unit still does not drain after the checks above. Water that leaks from the unit, or a problem that returns after each fix, means it is time to stop.

Our how to use a countertop dishwasher guide covers loading, cycles and emptying, which helps you rule out setup issues before you call. Call for help in these cases:

• The unit still does not drain after the hose, height, sink and filter checks.
• Water leaks from the unit or pools under it.
• The manual describes an error code that the checks above do not clear.
• The drain problem comes back after each fix.

Keep a note of what you tried and in what order. That record helps a repair pro find the problem faster.

A repair pro can check the internal parts, which are beyond a home check. Don't open the case or work on the wiring yourself.

Which fix to try first for a portable dishwasher not draining

Start with the drain hose, because a kink, a hose set too high or a hose that runs too long is the quickest check.

If the hose is clear and the unit is still not draining, check the sink and the filter next.

Pick the hose check first if the water sits in the tub. Pick a hose extension if the hose falls short of the sink and your manual allows a longer run.

Pick a cleaner if buildup is the likely cause and the spray arms look dirty. Pick a repair pro if the unit leaks or the problem keeps coming back.

If the drain is fine and you are still setting up the unit, how to hook up a portable dishwasher to your faucet covers that side of the job.

Frequently asked questions

Why is my portable dishwasher not draining?

The usual causes are a kinked or pinched drain hose, a hose set too high or run too long, a clogged sink drain or a dirty filter. Unplug the unit, check each one in that order, and follow your maker's manual for the height and length limits.

Can a drain hose extension help a portable dishwasher that will not drain?

It may help when the hose falls short of the sink, as long as your maker's manual allows a longer hose and the connection sizes match. It will not clear a clogged sink or a hose kinked at the unit, so contact the maker or a repair pro if water still stays.

Will a dishwasher cleaner help a slow drain?

It may help when buildup in the spray arms, filter or pipes is slowing the flow, but it will not clear a kink or a clogged sink. Finish says its liquid targets grease, hard water buildup and limescale, and that you should use it about every three months.

When should I call a repair pro for a dishwasher that will not drain?

Call the maker or a repair pro if the unit still won't drain after the basic checks, if water leaks from it or if the problem keeps coming back. Unplug the unit before any check, and don't open the case or work on the wiring yourself.