Project Guide

How to Install a Dishwasher

Difficulty: IntermediateTime: 2-4 hours Print

You can learn how to hook up a dishwasher when it’s time to replace the old one in your kitchen. The project doesn’t require any advanced plumbing or electrical skills. Installing a dishwasher successfully does require the proper know-how and equipment, including a dishwasher installation kit that has a 90-degree fitting and water supply line. This guide outlines how to install a dishwasher.


  • Adjustable Wrenches
  • Hole Saws
  • Pliers
  • Power Drill
  • Safety Glasses
  • Screwdriver Sets
  • Standard Level
  • Tube Cutting


  • Built-In Dishwasher
  • Dishwasher Connectors
  • Dishwasher Parts
  • Wire Connectors

1. Remove the Old Dishwasher

Before you begin removing the old unit, read the manufacturer’s instructions for how to install a dishwasher. It may contain information specific to your new appliance, such as additional parts that might be needed for the model.

  • Shut off the electricity to the dishwasher at the circuit breaker.
  • Turn off the water supply at the shut-off valve under the sink.
  • Use a screwdriver to remove the front access panel near the floor.
  • Disconnect the old wiring connections located in the terminal box.
  • Disconnect the old water supply line from the dishwasher using an adjustable wrench.
  • Place a shallow bowl underneath the connection to collect any water that leaks after you remove the nut.
  • Disconnect the drain hose from the dishwasher.
  • Remove the screws from the brackets that anchor the dishwasher to the bottom of the countertop and to adjacent cabinets.
  • Place a drop cloth or piece of cardboard on the floor in front of the appliance to avoid marring the floor.
  • Pull the old dishwasher out and move it from the area.
  • Tape the existing electrical cable to the floor so that it is not disturbed when the new dishwasher is moved into place.

2. Prepare for the New Dishwasher

Unpackage the new dishwasher near the installation location. Keep any carboard – or use another drop cloth – to protect your floor during the installation project.

  • Tip the new unit onto its back to have easier access to the plumbing and electrical connections.
  • Remove the front access panel.
  • Attach the 90-degree elbow fitting from the installation kit onto the dishwasher water valve, following the manufacturer’s instructions.

The installation kit also contains a new water supply valve.

  • Disconnect the old supply line from the shut-off valve.
  • Route the new supply line through the hole between the sink cabinet and the dishwasher installation location.
  • Temporarily secure the new water supply line to the floor with tape to prevent movement when the new dishwasher is pushed into place.
  • Attach the new water supply line to the shut-off valve.

Now work on the dishwasher drain hose.

  • Disconnect the old drain hose from the sink tail pipe or garbage disposal unit.
  • Route the new drain hose through the hole between the sink cabinet and the dishwasher.
  • Temporarily secure the new drain hose to the floor.
  • Attach the new drain hose to the sink tail pipe or disposal.

Note: Secure any slack in the drain hose to the rear of the sink cabinet. Be sure that it arches higher than the drain inlet to avoid backwash from the sink drain.

3. Connect Water, Drain and Electrical Lines

Tip the dishwasher upright and slide it into its space. Then, get on the floor to connect lines to the dishwasher.

  • Connect the water supply line to the 90-degree fitting, using pliers to ensure a tight fit.
  • Turn on the water supply, inspect for leaks and tighten connections if necessary.
  • Connect the drain hose according to manufacturer’s instructions.
  • Complete the electrical connections using wire nuts and following the installation guide.

With the water supply, drain and power lines attached, turn on the electricity at the circuit breaker and check the dishwasher’s operation before securing it into place.

  • Make sure that the front of the unit is flush with the cabinet fronts.
  • Use a level to ensure that the appliance is level and plumb so that it drains properly.
  • Adjust the leveling legs as necessary and tighten the locknuts.
  • Confirm the dishwasher’s placement and make any necessary adjustments.
  • Use the included brackets to secure the unit to the underside of the countertop and the adjacent cabinets.
  • Replace the front access panel.

Homeowners with a moderate amount of experience working with plumbing and electricity can learn how to install a dishwasher. If you need any necessary tools, dishwasher parts or other supplies, remember that The Home Depot delivers. Just say when, where and how. If installing a dishwasher is a bigger project than you care to do yourself, consider adding appliance delivery and installation service to your purchase.