Dishwasher not draining: causes and safe checks

Check carefully

Quick answer

Water left in the bottom of a dishwasher is usually caused by blocked filters, a clogged sink connection, or a kinked drain hose. After a new installation, a blanking plug left in the sink waste is a common culprit. Clean the filters, check the sink and hose, then check the pump under the filter. A broken pump needs an engineer.

Also covers: water in bottom of dishwasher · standing water in dishwasher · dishwasher won’t empty.

Likely causes

What you can safely check yourself

Stop and call a qualified engineer if:
  • The code or problem comes back after you’ve done the safe checks on this page.
  • The next step would mean removing a cover or panel, or working on the pump, valves, heater, motor, door lock or wiring. That is a job for a qualified engineer.
  • Water is leaking from inside the appliance or is near the plug or socket. Don’t touch the plug with wet hands or while standing in water. Switch off at the consumer unit instead.
  • The appliance is still under warranty. Contact the manufacturer first, because DIY work can affect your cover.

Work through these in order. Stop as soon as one of the signs above applies.

Clean the dishwasher filters

Before you start
  • Switch off and unplug the appliance at the wall socket before you touch hoses, filters or the back of the machine. Make sure your hands and the plug area are dry.
  • Wear protective gloves. Broken glass and sharp debris can collect in the filter and pump area, and it is hard to see.
Dishwasher filter assembly Twist to unlock, lift out Coarse filter Flat fine filter sits flat in the base Wear gloves: glass collects here. Refit until it locks.
Dishwasher filter assembly. Positions vary by model — check your manual.
  1. Take out the lower basket.
  2. Twist and lift the filter unit out of the base of the tub, then separate the parts as your manual shows.
  3. Rinse every part under running water. Use a soft brush for stubborn debris and nothing abrasive.
  4. Wipe food remains out of the sump area around the filter opening.
  5. Refit the filters so they lie flat and lock in position. On many models arrows line up when they are locked.

Don’t run the dishwasher without the filters fitted.

Check the sink waste connection

  1. Run the sink tap. If the sink drains slowly, the household drain is blocked, not the dishwasher.
  2. Check the spigot on the sink waste where the dishwasher hose connects isn’t clogged with food debris.
  3. If the dishwasher was just installed or moved, check the blanking plug was removed from that spigot.
  4. If the hose connects to a waste disposal unit, check the plug in the disposal unit’s dishwasher inlet has been removed.

Check the dishwasher drain hose

Before you start
  • Switch off and unplug the appliance at the wall socket before you touch hoses, filters or the back of the machine. Make sure your hands and the plug area are dry.
  1. Where you can see it (usually under the sink), check the drain hose isn’t kinked, twisted, squashed or damaged.
  2. Check its length and the height of the drain connection against your manual. Hoses that are too long, too low or too high drain badly.

Don’t pull a built-in dishwasher out of its housing. If the hose can only be reached that way, ask an installer or engineer.

Clear the drain pump under the filter Take care

Before you start
  • Switch off and unplug the appliance at the wall socket before you touch hoses, filters or the back of the machine. Make sure your hands and the plug area are dry.
  • Wear protective gloves. Broken glass and sharp debris can collect in the filter and pump area, and it is hard to see.
  • Never force a locked door, a stuck filter cap or a seized part. Forcing it usually causes more damage.
  1. Only do this if your manual shows a user-removable pump cover or valve under the filter. Not every dishwasher has one.
  2. With the dishwasher off and unplugged, take out the lower basket and the filters.
  3. Soak up or scoop out the standing water with a sponge or small cup.
  4. Release the pump cover as your manual shows (Bosch, for example, uses a teaspoon to lever it off).
  5. Remove any glass, fruit stones or other debris you can see, and check the pump impeller turns freely.
  6. Refit the cover until it clicks or sits flush, then refit the filters and basket.

Don’t use an electric screwdriver on the pump cover.

Don’t put your fingers into the pump opening. Use the spoon or tweezers, with gloves on.

Don’t go any further than the cover your manual shows. The pump itself, its motor and wiring are an engineer job.

Showing an error code?

These codes are related to this problem. Codes differ by brand, so pick yours:

Step-by-step guides

Related problems

Brand guides: AEG, Bosch, Miele, Samsung. More dishwasher problems and codes, or use the fault finder.

Sources

Last checked against these sources: .

We write every page in our own words from manufacturer guidance and check it against the sources above. If your manual says something different, follow your manual. How we check.