What To Do If Your Dishwasher Is Not Draining

Woman unloading dish washer in kitchen.
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Is your dishwasher not draining completely? Although you first thought might be that the dishwasher needs to be repaired or replaced, the problem could actually be with the plumbing and not the machine. If the water from the dishwasher encounters a blockage on its way to the drain pipe, it will have nowhere to go but back into the dishwasher. So, if your dishwasher is not draining, rule out a stoppage by following these steps.

  1. Make sure the sink is draining. If your sink is not draining well the dishwasher will not drain either.
  2. Run the garbage disposer. In most cases the dishwasher is set up to drain through the garbage disposer. When there is food built up on the inside of the disposer or when the disposer is clogged there is less space for the dishwasher water to go. Run the disposer thoroughly with plenty of water to really clear out the debris inside of it.
  3. Clean the air gap. If water comes out of the air gap (and sometimes all over the counter) when you run the dishwasher, the blockage is between the air gap and the garbage disposer. To clear it, remove the air gap cap, locate the large tube that goes into the garbage disposer and remove it. Clear out any build up in the tube.
  4. Check the dishwasher drain connection. Look at the connection between the drain tube and garbage disposer. While the air gap tube is out you can check to see if the blockage is at the opening to the garbage disposer. Insert a screw driver into the small opening for the drain tube and move it around to make sure it is clear.
  1. Clear the drain tube. Disconnect the drain tube from the air gap and make sure it is not plugged. If there is any debris inside the tube, clear it out before reconnecting it.

If you have tried all of these fixes and the dishwasher is still not draining it could be that the pump is bad. If this is the case you can contact an appliance repair person to inspect it.