If you notice water seeping out from underneath your sink while the dishwasher is running, you should check your dishwasher hose as soon as possible. The problem could be simple, such as a loose connection, or the hose might be damaged or split, which means that it should be replaced. In either case, the repair isn't difficult and no plumbing-specific tools are required.
To operate, your dishwasher needs water, electricity and some way to drain the used dishwater. The dishwasher gets its water by connecting to a supply valve at the nearest water connection, which in most cases is usually the kitchen sink. Under the counter, dishwashers hook up to the home's electrical supply through a panel on the bottom of the unit. A drain hose carries the used dishwater from the dishwasher to the drain underneath the sink.
The drain hose is usually hidden from view and is typically routed through cabinets before reaching the kitchen sink. The middle part of the hose is elevated and clamped in place along the wall or cabinet to help prevent backflow through the drain hose. The drain hose can be connected to the dishwasher tailpiece or, in homes so equipped, to a disposal underneath the sink.
The first thing to do when a leak is spotted is to turn off the dishwasher, usually by opening it up. Cut the power for the dishwasher at the main circuit breaker, which will help prevent accidental shock, especially when there is water present. Turn off the water supply for the dishwasher at the supply valve beneath the sink to prevent further leaks. Wipe up any spilled water with a towel.
If your hose is leaking underneath the sink and nowhere else, check the connection where the hose meets either the disposal or tailpiece under the sink. Tighten the clamp in this location to see if that solves the problem. If needed, install a new hose clamp to the hose and secure. Run the dishwasher to see if this solves the problem.
Replacing the Dishwasher Hose
If tightening or replacing the clamp doesn't solve your leak, chances are there's a hole in your dishwasher line somewhere and the line should be replaced. Loosen the hose clamp holding the hose in place underneath the sink and pull the hose off the inlet nipple. Follow the hose back to the dishwasher, removing any hose clamps along the way. Loosen the kick panel at the bottom of the dishwasher, just beneath the door, and pull it out of place. Look underneath the dishwasher and locate where the drain hose connects to the pump. Remove the clamp in at this connection. Slip the end of a new hose over the pump nipple. Run the hose back to the disposal or sink connection and secure with another hose clamp. Elevate the center portion of the hose and secure with a clamp. Test the hose for leaks by running another load. Tighten the hose clamps if needed.