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Dishwasher Not Draining: Causes & Fixes

Standing water in the tub.

Food debris, grease, or objects trapped in the dishwasher filter or sump area can block the drain path and cause standing water; Whirlpool, GE, Samsung, LG, and iFixit all document this as a leading cause.

Before you work on your dishwasher

  • Power: Unplug the dishwasher or switch off its circuit breaker before removing panels or touching wiring.
  • Water: Turn off the water supply valve before disconnecting hoses or the inlet valve.
  • Heat: Water and the heating element can be hot right after a cycle; let the dishwasher cool first.
  • Sharp debris: Wear gloves when reaching into the filter or sump; broken glass often collects there.
  • Stop: If you smell burning, see smoke or sparks, or find water near wiring, switch off the breaker and call a technician.
  • Disconnect power before accessing internal dishwasher parts: Unplug the dishwasher or switch off the circuit breaker that powers it before removing panels, the filter, or the drain pump cover, or before reaching into the sump.
  • Shut off the water supply before disconnecting hoses: Turn off the water supply before disconnecting the drain hose, siphon connection, or water inlet, or before pulling the dishwasher out for service.
  • Hot water and steam scald risk: Open the dishwasher door carefully during or right after a cycle. Hot water or steam can escape and cause burns; wait until water noises stop and steam subsides before fully opening the door.
  • Sharp debris near the filter and drain pump: Wear gloves and use caution when removing the filter, pump cover, or other parts for cleaning; broken glass or other sharp debris can collect near the drain pump impeller.

Why your dishwasher is not draining

  1. Filter or sump clogged with food debris: Food debris, grease, or objects trapped in the dishwasher filter or sump area can block the drain path and cause standing water; Whirlpool, GE, Samsung, LG, and iFixit all document this as a leading cause. Difficulty 1/5.
  2. Drain hose kinked, crushed, or pinched: A kinked, crushed, or sharply bent drain hose restricts water flow and is a documented cause of a dishwasher not draining, cited by Whirlpool, Samsung, GE, LG, and iFixit. Difficulty 2/5.
  3. Cycle interrupted or left paused before draining: What looks like a dishwasher that won't drain is sometimes a cycle that was interrupted or left paused before it reached the drain step; iFixit and Frigidaire both list this as a check before assuming a mechanical fault. Difficulty 1/5.
  4. Garbage disposal or household sink drain clogged: A clogged garbage disposal or a slow/blocked kitchen sink drain that the dishwasher shares a drain path with can prevent the dishwasher from draining, per Samsung and GE. Difficulty 2/5.
  5. Sink air gap clogged with debris: A sink air gap clogged with debris buildup can restrict drainage and cause water to remain in the dishwasher tub; documented by GE and referenced in LG's air-gap cleaning step. Difficulty 1/5.
  6. Garbage disposal knockout plug not removed: On a newly installed dishwasher connected to a garbage disposal, the disposal's dishwasher-drain knockout plug is sometimes left in place by the installer, blocking drainage; GE, LG, Frigidaire, and iFixit document this. Difficulty 2/5.
  7. Drain hose high loop too low or too long: A drain hose (or high loop) installed lower than the manufacturer's required height, or longer than the maximum allowed length, lets water siphon back into the tub instead of draining; documented by GE, LG, and Frigidaire, each with its own height/length specification. Difficulty 2/5.
  8. Over-sudsing from wrong or excess detergent: Using the wrong type of detergent (such as regular dish soap) or too much detergent can cause over-sudsing that interferes with the dishwasher's ability to drain, per GE. Difficulty 1/5.
  9. Drain pump jammed or failed: A jammed, blocked, or failed drain pump/impeller can leave water standing in the tub; Whirlpool's diagnostic guidance and iFixit's sound-based diagnostics both point to this when the pump hums or buzzes without moving water. Difficulty 3/5.

Find the cause for your dishwasher

Before anything else: do you see water near the power cord or outlet, or smell burning or see smoke?

Step-by-step checks for a dishwasher not draining

Check the sink air gap for debris

About 5 minutes

  1. Locate the air gap cap on the sink or counter, if present.
  2. Remove the cap and check inside for debris blocking the passage.

Check whether the cycle actually finished

About 2 minutes

  1. Look for a lit 'Clean' indicator or check the display for a delay/pause state.
  2. If the cycle was interrupted or paused, note this before assuming a mechanical fault.

Check detergent type and amount

About 3 minutes

  1. Confirm the product used is a detergent made for automatic dishwashers, not dish soap.
  2. Confirm the amount used matches the package recommendation.
  3. Open the door after a cycle and look for visible foam or suds above the filter.

Run the disposal and test the sink drain

About 5 minutes

  1. Run the garbage disposal to clear food waste.
  2. Run the kitchen faucet for about 30 seconds.
  3. Watch whether the sink itself drains normally.

Inspect and clean the filter and sump

About 10 minutes

  1. Remove the lower rack.
  2. Twist and lift out the filter assembly.
  3. Check the filter screen and the sump beneath it for standing water, food debris, or foreign objects such as broken glass.

Inspect the drain hose for kinks or crushing

About 5 minutes

  1. Trace the drain hose from the dishwasher to the sink or disposal connection.
  2. Check for kinks, crushed sections, or the dishwasher cabinet itself resting on the hose.

Listen for drain pump sounds during the cycle

About 10 minutes

  1. Run a cycle and listen during the drain phase.
  2. Note whether the sound is a steady hum/buzzing, a squeal/drone, a scraping noise, or normal pump operation.

Check the drain hose high loop height and length

About 10 minutes

  1. Measure the height of the drain hose's highest point above the floor.
  2. Measure the total run length of the drain hose.
  3. Compare both to the appliance's installation instructions.

How to fix a dishwasher not draining

Clean the sink air gap

About 10 minutes · Difficulty 1/5

  1. Remove the air gap cap on the sink or counter.
  2. Clear out accumulated debris with a toothpick or small brush.
  3. Reassemble the cap.

Clean the filter and sump

About 10 minutes · Difficulty 1/5

  1. Remove the filter assembly and rinse it under warm running water.
  2. Remove visible food debris and grease from the sump beneath it.
  3. Reinstall the filter, locking it into place.

Cancel and restart the cycle

About 5 minutes · Difficulty 1/5

  1. Press and hold the Cancel/Reset button per the owner's manual (typically a few seconds).
  2. Select a new cycle and press Start.

Switch to the correct detergent type and amount

About 2 minutes · Difficulty 1/5

  1. Stop using regular dish soap or oversized detergent doses.
  2. Use a detergent made for automatic dishwashers in the amount recommended on the package.

Clear the garbage disposal and household drain

About 15 minutes · Difficulty 2/5

  1. Run the garbage disposal to clear food waste.
  2. If the kitchen sink itself is slow to drain, clear the household drain line (or have it professionally cleared) before retesting the dishwasher.

Correct the drain hose loop height and length

About 20 minutes · Difficulty 2/5

  1. Reroute or re-secure the drain hose's high loop so its highest point meets the manufacturer's minimum height.
  2. Trim or reroute the hose if it exceeds the maximum specified length.
  3. Secure the loop to the underside of the counter.

Clear and straighten the drain hose

About 20 minutes · Difficulty 2/5

  1. Loosen the clamp and detach the hose from the disposal or sink tailpiece.
  2. Flush the hose with warm water to clear debris.
  3. Straighten any kinks or crushed sections and remove anything pressing on it.
  4. Reconnect the hose and secure the clamp.

When to call a technician about a dishwasher not draining

  • Remove the garbage disposal's dishwasher-drain knockout plug
  • Have a jammed or failed drain pump serviced

Sources

  1. Dishwasher SP.. Instruction Manual, Bosch Home Appliances US (retrieved 2026-09-18)
  2. Dishwasher SHSM63****, SHS863****, SHS843****, SHVM63****, SHV863**** Operating Instructions, Bosch Home Appliances US (retrieved 2026-09-18)
  3. Dishwasher SMS6HAI01A User Manual, Bosch Home Appliances US (retrieved 2026-09-18)
  4. What can I do if my dishwasher is not draining?, Frigidaire / Electrolux (retrieved 2026-09-18)
  5. Dishwasher - Not Draining, GE Appliances (retrieved 2026-09-18)
  6. Dishwasher Not Draining - iFixit Troubleshooting, iFixit (retrieved 2026-09-18)
  7. How to Fix an LG Dishwasher That Is Not Draining (OE Error), LG Electronics USA (retrieved 2026-09-18)
  8. Samsung dishwasher is not draining, Samsung Electronics America (retrieved 2026-09-18)
  9. Dishwasher Not Draining - Product Help, Whirlpool Corporation (retrieved 2026-09-18)

Last updated September 29, 2026 · facts last verified September 19, 2026 · How we source and verify

Guidance only; follow your appliance manual and local codes. If anything looks unsafe, stop and call a qualified technician. Safety disclaimer