How to Install a Dishwasher
Our pros tell you how to avoid the most common mistakes when learning how to install a dishwasher.
A full day
Less than $20
IntroductionThis step-by-step guide shows you how to swap out your old dishwasher and make the new water, drain and electrical connections.
- 4-in-1 screwdriver
- Adjustable wrench
- Voltage tester
- Braided stainless steel water line (optional)
- Teflon tape
Getting Started: How To Install A Dishwasher
Dishwasher installation isn’t terribly challenging. In most cases, you won’t need any special tools or skills.
Most dishwashers are 24 inches wide, so you won’t have to alter cabinets to get the new one to fit. If you change sizes, you’ll have to alter your cabinets. This requires more advanced carpentry skills that we won’t show here.
You may find extra layers of flooring raised the floor height in front of the old dishwasher. This can make it difficult to remove the old one and install the new one. In some cases, you may need to loosen the countertop or remove flooring. Consider consulting a dishwasher installation professional if you don’t feel confident about the best strategy.
Get a blanket, an old rug or cardboard to protect your floor while you work. Gather two adjustable wrenches, a screwdriver, a tape measure, a pair of pliers and a level. You’ll also need a shallow pan, bucket, sponge and rag to collect water that will drain from the lines when you disconnect them.
Turn off the power to the dishwasher at the main panel or unplug it under the sink. Also, turn off the water to the dishwasher at the nearest shutoff valve, usually the hot water one under the sink. Or shut it off at the water heater.
Consider removing the cabinet doors from your sink base to make disconnecting the drain lines easier.
If you have aluminum wiring, call in a licensed electrician certified to work with it. This wiring is dull gray, not the dull orange that’s characteristic of copper.
Project step-by-step (12)
Remove the front panel
The water and electrical connections are underneath the dishwasher, behind a lower front panel you have to unscrew. Always test with a voltage detector to make sure the power is off.
When you remove the electrical line from the box, leave the cable clamp on and reuse it on the new dishwasher. Sometimes dishwashers are plug-and-cord connected rather than “hard-wired”. If so, disconnect the cord and reuse it on the new dishwasher. If it’s in bad condition, buy a new one from an appliance dealer.
Disconnect the water supply
Usually, the water supply line is flexible copper or braided stainless steel. In either case, remove the nut securing it to the 90-degree fitting on the dishwasher.
As long as the nut and ring are in good condition (no nicks or gouges), leave them on the line for later reuse. Remove the 90-degree fitting for use on the new dishwasher. It’s important to orient it exactly the same direction on the new machine so the water line feeds directly into it.
You can bend the copper line slightly, but take care not to kink it. If you do, you’ll have to replace it. Flexible stainless steel lines are a good replacement, available at a hardware store or home center. Make sure you buy them long enough and with fittings that match the old.
Disconnect the drain
Sponge out any standing water inside the dishwasher before removing the drain line under the sink. It’s the flexible hose clamped to an inlet arm on the sink drain or a garbage disposer.
As you slide the old dishwasher out, you’ll have to simultaneously work the drain hose back through the hole in the sink cabinet. Keep a rag handy to wipe up the water that will run out of the line.
Pull the dishwasher out
Lowering the dishwasher gives you more clearance to slide it out. Chances are the leveling feet will be difficult to turn, but a shot of penetrating oil on the threads may make it easier.
If you need more clearance, cut off the feet with a hacksaw blade and turn the screw out. Then be sure to slip cardboard or a rug under them to avoid gouging your floor.
Screw on the water valve
Uncrate the new dishwasher according to the instructions in the box. Inside, you’ll find the manuals and installation instructions. Review the instructions before proceeding; they may differ slightly from the details we show.
Wrap the 90-degree fitting twice with Teflon tape and screw it into the new water valve. Tighten it, aiming the elbow as on the old machine. Tip the dishwasher on its back and attach the 90-degree fitting.
Attach the drain line
Don’t reuse your old drain hose; the dishwasher will come with a new one. To prevent clogged drains from flooding the dishwasher, be sure to loop the flexible drain line all the way up to the bottom of the countertop.
Some plumbing codes require a special air gap fitting in the drain line. Call your local plumbing inspector to find out the rules.
Adjust the dishwasher feet
Lay the dishwasher water supply line, drain and electrical lines flat on the floor. The manual will tell you how to adjust the leveling feet and/or wheels to fit the height of the opening. It’s easiest to set these before sliding in the dishwasher.
Make minor adjustments after the installation. But if your kitchen floor is built up higher than the area where the dishwasher sits, you’ll have to adjust the feet after you slide it into the opening.
If your dishwasher comes with rear wheels without adjusters in the back, you may have to set shims to raise the back to the height of the finished floor. Tack them to the floor so they don’t shake loose when the dishwasher runs.
Slide the new dishwasher in
Slide the new dishwasher in, grasping it by the sides to avoid denting the front panel. Set the dishwasher in position. but don’t secure it to the countertop yet. Wait until you make all connections and adjustments.
Align the dishwasher
Slide the dishwasher back until it’s flush to the cabinets. Positioning may vary slightly according to dishwasher styles and the style of your cabinets.
Level the dishwasher
Adjust the leveling feet with a wrench until the dishwasher is level (side to side) and plumb (up and down).
Attach the dishwater supply line
Connecting the copper water line so it doesn’t leak can be tricky. The secret is aligning it so it slides straight into the threaded part of the elbow. If it’s cocked to one side, the compression nut won’t thread on right and it will leak.
If necessary, turn the elbow on the dishwasher slightly with a wrench to align it, or gently bend copper lines about eight to 12 inches from the end.
With the dishwasher water supply line, the electrical cable and drain connected, turn the power and water back on and check for leaks. Recheck the positioning, then screw the dishwasher to the countertop (some screw to the cabinet sides).
If your countertop is a synthetic material or stone and the old holes don’t line up, follow the directions listed in the manual.
Finish the drain and electrical connections
Clamp the dishwasher drain hose to the dishwasher. Then clamp the electrical wires and connect them. Finally, screw the dishwasher to the countertop bottom.
How long does it take to install a dishwasher?
On average, a professional dishwasher installation can take anywhere from 1 to 4 hours. The time it takes to install a dishwasher can vary depending on several factors, including your level of experience with plumbing and electrical work, the complexity of the installation, and whether you encounter any unexpected dishwasher problems.
Who installs dishwashers?
There are several national companies that offer dishwasher installation services for homeowners. Companies such as Best Buy, Lowe’s, Home Depot, Sear’s Home Services, Angi, Thumbtack and Amazon Home Services have teams of trained professionals who can handle the installation process efficiently and according to industry standards.
When hiring a national company or a local professional for dishwasher installation, it’s essential to check their credentials, reviews, and pricing. Ensure that they are licensed, insured, and experienced in appliance installation to guarantee a smooth and safe installation process.
Can a portable dishwasher be permanently installed?
Yes, a portable dishwasher can be permanently installed with some modifications. To do this, you’ll need to convert it from a temporary setup to a more permanent one by creating a stable connection to your kitchen’s plumbing and electrical systems.
This typically involves removing the faucet adapter and installing a direct water line, as well as ensuring a dedicated electrical connection. Additionally, you may need to secure the dishwasher in place to prevent any movement during operation. Keep in mind that this process may vary depending on the specific model of your portable dishwasher, so always refer to the manufacturer’s instructions and, if needed, consult a professional for expert advice.