Installing a Dishwasher


Once you have the site prepared, installing a dishwasher is easy. Make the opening the correct size and test-fit the dishwasher. The cabinets on either side should be spaced according to manufacturer's instructions -- usually 24-1/4 inches.

Run an electrical cable -- armored or nonmetallic, as required by code -- to the space. Make sure it will not bump into the dishwasher's frame. A 14/2 cable is adequate for a 15-amp circuit. Make sure the dishwasher will not overload the circuit. Hire an electrician if you are unsure.

Most dishwashers come with a drain hose. The drain hose runs to an air gap mounted to a knockout hole in the sink. From there, another length of hose runs to the garbage disposer. If there is no garbage disposer, the hose runs to a dishwasher tailpiece on the trap.

The water supply line is typically flexible copper, connected to its own shutoff valve.

Prestart Checklist

About an hour once the electrical and plumbing lines are run and the cabinets installed

Tubing cutter, drill, screwdriver, adjustable wrench, wire strippers, groove-joint pliers

Making simple plumbing and electrical connections

Install the electrical and plumbing lines; install the cabinets and countertop; cut a 1-1/2-inch hole in cabinet for drain hose and supply line.

Dishwasher with drain hose, flexible copper supply line, hose clamps, air gap, electrical cable, wire nuts

Step 1

Using a tubing cutter trim the water supply line to the necessary length. Make sure the electrical cable is long enough to reach the junction box built into the dishwasher.

Step 2

Push the dishwasher into the opening. As you do so, thread the drain hose through the 1-1/2 -inch hole already cut in the cabinet. Make sure the lines do not become kinked or bent.

Step 3

Slip a nut and ferrule onto the end of the supply line. Carefully bend the tubing and insert it into the dishwasher's supply inlet. Slide the ferrule down into the inlet and tighten the nut. Open the stop valve and check for leaks; you may need to tighten the nut further.

Step 4

Run the drain line to the air gap, then to the garbage disposer or a tailpiece with a special dishwasher drain fitting. Slide a hose clamp onto the hose, slip the hose onto the fitting, slide the clamp over the fitting, and tighten the clamp.

Step 5

Run the electrical cable through the cable clamp and tighten the clamp nuts to hold the cable firm. Strip and splice wires -- black to black, white to white, and ground (green or copper) to ground. Cap each splice with a wire nut and install the electrical cover plate.

Comments (7)
bioblakeyahoo wrote:

my dishwasher electrical supply is an outlet under the sink......Can I run the electrical cable (spliced to the dishwasher electrical box)through the same 1.5 inch hole with the drain hose and water supply hose?

11/5/2015 10:15:52 AM Report Abuse
Bkj1720 wrote:

Not receiving power to the Dishwasher

2/15/2011 06:04:31 PM Report Abuse
dufus_dan wrote:

what problems can pop up if you bypass the airader and connact directly to the disposal

1/6/2011 03:02:09 PM Report Abuse
delgadojleng wrote:

you said only three conections,what about the airader?

12/16/2009 01:00:52 PM Report Abuse
smedleyras wrote:

thank you

11/14/2009 08:12:34 AM Report Abuse
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