A puddle after yesterday’s plumbing work

Take a picture of the water before starting another wash. Note whether it covers the flat tub floor or sits only down in the filter recess. Check the manual for your model’s normal resting water level. A photo taken immediately after the drain cycle is more useful than a description of a puddle discovered the following morning.

Follow the route from tub to sink

In a kitchen where the dishwasher drains into a garbage disposal, the drain water travels along the hose to a small inlet on the disposal. A new disposal comes with that inlet plugged. If the dishwasher hose was attached while the plug was still inside, the outside of the connection can look finished even though the water has nowhere to go.

Tub → drain hose

The pump sends used water toward the sink cabinet.

Hose → disposal inlet

A plug left inside a new inlet blocks that route.

Inlet → sink drain

A sink that also backs up gives the plumber another clue.

What to check without taking the machine apart

Does the sink itself empty normally? Is the visible hose pinched by a bin or cabinet contents? Did water stay in the tub immediately, or did it drain and return later? Write those answers down. If the problem started after the disposal was fitted, ask the installer to check the inlet plug and hose routing. Leave the hose attached and the appliance in place for that visit.

If nothing under the sink has changed

Consult your model’s instructions for cleaning a user-removable filter. Disconnect power before handling it and avoid reaching into the pump. If water remains after the manufacturer’s drain procedure, give the technician the model number, photo and any displayed error code. Stop using the appliance if water is escaping onto the floor or the breaker trips.

For more detail, see Whirlpool’s dishwasher drainage guide. Related reading: the under-sink leak checklist.