How to Replace a Dishwasher

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What You'll Need
Screwdriver (phillips and flat head)
Adjustable wrench
Electrical tape
Needle-nose pliers
Voltage tester
Slip-joint pliers
Wire nuts
Teflon® tape

It's been shown that dishwashers use less water than conventional hand washing. And, new energy-efficient models are better than their old counterparts at saving both energy and water.

If you haven't upgraded because you were afraid to install a dishwasher or didn't want to pay a fortune to have someone install one for you, then you're in luck. This how-to guide will show you how you can easily install a new dishwasher or replace your existing one with minimal difficulty.

If you're installing a new dishwasher, there are a few things you need to have in order to complete the job. First is an electrical outlet under the sink or an available circuit rated at 20 Amps coming directly from the electrical panel. Second is a water supply and drain close by. Third is the space available for a new dishwasher. You may need to remove some under counter cabinets or floor tiles in order to fit the new dishwasher. If you're replacing an old dishwasher, then it's no problem because the space is already there.

Remove the Old Dishwasher

The first step is to remove the old dishwasher. Make sure to measure the old dishwasher so you can buy the right size when choosing the new one.

Step 1 - Turn the Power and Water Off

Turn the electrical circuit that supplies power to the dishwasher OFF. You can unplug it if it's within reach. Close the water valve that supplies water to the dishwasher.

Step 2 - Pull Out the Old Dishwasher

Unscrew the two screws holding the dishwasher to the countertop. These screws are located right in front of the dishwasher. Gently slide the dishwasher out from under the counter.

Step 3 - Remove the Junction Box Cover

Follow the electrical cord to the junction box, usually on the lower rear side, and remove the cover.

Step 4 - Disconnect the Wiring

Use a voltage tester to ensure the circuit is OFF and disconnect the wiring. Remove the electrical cord from the junction box and place wire nuts on the ends of each wire, then move the wires so they won't be in the way.

Step 5 - Remove the Water Line

Locate the water inlet line under the dishwasher. Remove the nut holding it in place and remove the water line. (Keep a towel handy to soak up any draining water still in the line).

Step 6 - Disconnect the Drain Line

Under the sink, locate the dishwasher's drain line and disconnect it from the sink's drain line or garbage disposer.

Step 7 - Remove the Dishwasher

Now that the dishwasher is completely disconnected, remove it and clean out the area before installing the new one.

Install the New Dishwasher

Step 1 - Attach the Drain Line

Gently place the dishwasher on its back and attach the drain line with the supplied compression clamps. You may need needle-nose pliers to help open the clamps.

Step 2 - Connect the Water Line

Wrap Teflon® tape around the threads on the water inlet connection and connect the 90 degree brass fitting needed to connect the water line. Then set the dishwasher upright and connect the water line to the 90 degree fitting.

Step 3 - Adjust the Retaining Sleeve

Underneath the dishwasher, you will see a retaining sleeve for the electrical cord to slide through. Slide the cord through and tighten the sleeve.

Step 4 - Run the Electrical Wires

Remove the cover from the junction box and run the wires through the knockout into the box. Connect the black wire to black wire, using the needle-nose pliers to twist the pair together, and then tighten a wire nut over them. Do the same thing to the white wires. The green or bare ground wire gets tightened to the green ground screw inside the box. Wrap electrical tape around the wires where the wire meets the wire nut. Replace the junction box cover.

Step 5 - Connect the Drain Line

Connect the dishwasher's drain line to the exact spot that the old one was connected, either to the drain line or to the garbage disposer.

Step 6 - Check for Water Line Leaks

Before moving the dishwasher into place, open up the water line to check for leaks.

Step 7 - Slide the Dishwasher into Place

Finish sliding the dishwasher into place under the counter and use a level to make sure that it's sitting level. Adjust the legs on the unit to make any corrections.

Step 8 - Attach the Dishwasher to the Counter

Screw the top flange of the dishwasher into the bottom of the counter to hold it in place. Install the bottom cover.

Step 9 - Turn the Power On

Turn the power back on to the circuit or plug in the electrical cord.

Step 10 - Run a Cycle

With the dishwasher empty, run a cycle and double check again for any leaks.

If you wish to know a little more about how a dishwasher works, check out this companion article by clicking here. Likewise, if you have a dishwasher that's acting up, click here to see if there may be an easy solution to your problem before buying a new one or paying a plumber to fix something you may be able to repair yourself.