How to Install a Dishwasher
Sometimes, that old dishwasher that comes with your new home is in desperate need of an upgrade. Fret not because taking out the old malfunctioning dishwasher and installing a shiny brand new one is something even those unfamiliar with the plumbing world can do.
While there are those cases of moving a dishwasher that justify a professional or the even rarer situation of “I’ve never seen this before” that definitely warrant an experienced plumber, you can learn how to install a dishwasher in just a few steps.
Read the Manufacturer’s Instructions
It’s tempting to skip over the thick booklet that comes with your new dishwasher but make time to leaf through it before you get started. Your new appliance may have additional accessories requiring a special step or two to install them. There also might be pertinent information for the installation process unique to your dishwasher.
Here's what you'll need:
- Pliers
- A level
- Teflon tape
- Adjustable wrenches
- Screwdriver and screwdriver sets
- Tube Cutters
- Your new dishwasher, the parts that come with it, and the manual
Remove the Old Dishwasher
Now for the cathartic removal process of finally ditching that clunky old dishwasher. Most dishwashers are a standard size of 24 inches wide, so you probably won’t have to demo any cabinets. If you do, you’ll want to call a carpenter — or choose a different model to make your life easier.
Step One: Prep Work
- Head to the circuit breaker and shut off the electricity that powers your dishwasher — no need to get shocked during this project.
- Turn off the water supply to the dishwasher. This should be located under your sink in the form of a shut-off valve.
Step Two: Disconnect
- Remove the front access panel of the dishwasher located near the floor. Use a screwdriver to take it off. This is where the electrical and water connections are housed.
- Disconnect the dishwasher’s wiring connections (inside of the terminal box) and the water supply line. To disconnect the waterline, use an adjustable wrench (typically, these lines are copper or braided steel). Disconnect the drain hose. There might be lingering water, so grab a bowl or some towels to catch anything before you take off the nut.
Step Three: Removal
- Remove the dishwasher unit by unscrewing the brackets from the bottom of the countertop and to the neighboring cabinets.
- For sensitive floors, you’ll want to cover your work area with a moving tarp, sturdy cardboard, or that old rug you hate anyway so you don’t scrape the surface as you haul the unit out.
- Say goodbye to that old appliance, and be sure to tape up any hanging electrical cables so they don’t get in the way.
Installing the New Dishwasher
Step One: Prep Work
- Get the new dishwasher ready to go by following the instructions. Because you’re diligent, you’ve already gone through the step-by-step instructions that came with the dishwasher, and you’re aware of the process.
- Attach the 90-degree fitting that came with the installation kit onto your new dishwasher’s water valve. You’ll need to tip the dishwasher on its back to do this, and it won’t hurt to wrap the fitting with some Teflon tape.
Step Two: Drain Line and Water Supply Valve
- Grab your new drain line that came with the dishwasher and ditch the old one because it could cause sink clogs and potential flooding. Thread the drain line into the sink base, looping it all the way to the bottom of the countertop.
- Your new dishwasher also comes with a new water supply valve. Place the new supply line through the hole located between the cabinet and the dishwasher installation spot. Then, attach the water supply line to the shut-off valve.
Step Three: Setting in Place and Reconnecting
- Move the dishwasher into place by handling its sides, so you don’t dent the front panel. Avoid future leaking by aligning its sides straight into the threaded section of the elbow to ensure a secure fit. Use a level to help determine the appliance is level and will drain correctly.
- Connect the dishwasher’s supply line into the 90-degree fitting (use pliers to tighten it), attach the drain hose (follow your instruction booklet if needed), and connect the electrical wiring.
Step Four: the Double-Check
- Finally, turn the electricity back on at the circuit breaker. Check to make sure the dishwasher is flush and level. If it all looks good, secure the appliance into place with the brackets that came with it and replace the front access panel.
When to Call the Pros
For most homeowners, installing a new dishwasher is an afternoon DIY project that demands little to no plumbing knowledge, fancy tools, or electrical know-how. It’s cheaper and feasible to install a new dishwasher yourself.
However, not all of us are lucky. If you’ve got an old house that has proved time and time again that things are cobbled together behind the walls and appliances, you might want to grab a number for a professional plumber.
If you’re moving a dishwasher’s location, if the kitchen floor is built up and is higher than where the dishwasher will sit, or if the plumbing codes where you live require a special air gap fitting in the drain line, then call a professional.
It’s a small cost to avoid such headaches and having to wash the dishes by hand.