What could cause water back up into dishwasher?

Answer by  ApprenticeJenn (959)

There is either a partial or full clog in the dishwasher drain system or the water pump is not functioning correctly.

Answer by  Halpern (63)

Generally, a dishwasher empties into the same drain as the kitchen sink. A blockage in that drain line (especially the u-joint) would affect the dishwasher.

Answer by  BeefStrule (690)

There's probably some faulty plumbing going on there. Check to see if the hinge bearings have come loose. If they have, you might want to call a professional as it can be a tricky job.

Answer by  TheScientist (86)

The drain coming from the dishwasher is almost certainly blocked at some point. Try using a drain de-clogger as directed, then run the dishwasher a few cycles.

Answer by  TheRealPlumber (249)

The most common cause of a water back up into a dishwasher would be to not have a check valve installed at the drain tail piece or the dishwasher discharge hose was not installed above the dishwasher housing as per the manufacturers rewcommendations. This should be corrected as soon as possible and could lead to greater problem with your unit.

Answer by  HelpfulAndy (1107)

You may have a slight clog in the line somewhere. Get some draino and drop it down the sink closest to the dishwasher. If that doesn't work, your line may be too small.