Turn off the circuit breaker to the Hotpoint dishwasher. Although you are not working with electrical parts directly, it is a safe practice to disconnect power before working on the appliance.
Open the Hotpoint dishwasher door and pull the lower dish rack out of the unit. Rotate the lower spray arm so you have unobstructed access to the filter housing. The housing is the raised box behind the spray arm with holes in the sides.
Remove the two screws securing the filter housing to the bottom of the tub with a 5/16 inch nut driver or socket wrench. Lift the filter housing out of the dishwasher.
Pull the filter out of the sump hole in the bottom of the dishwasher. Hold the filter under running water and rinse off any food particles and debris.
Reach inside the sump hole and pull out any debris with your fingers. Insert the filter back into the sump hole.
Place the filter housing over the filter and line up the mounting holes. Secure the housing to the bottom of the dishwasher tub with the retaining screws.
Slide the lower dish rack back into the dishwasher and close the door. Turn on the circuit breaker to power the Hotpoint dishwasher.