Oh yes! Finally you've gotten a new dishwasher and you've decided to install it yourself. But before you shove it into the cabinet opening, there are a few things you'll have to prepare before the dishwasher can be installed. For instance, a dishwasher will need its own dedicated circuit run from the electrical panel. It also needs a source of hot water and a drain to connect to. Dishwashers require a 24" cabinet opening in order for it to fit. Try placing the dishwasher next to the sink for convenience. That way, the water and drain are in close proximity to the dishwasher.
Installing the Feed
The first step is to install a 20-amp circuit from the circuit breaker panel, if one is not already installed. If it is, be sure that the power is turned off to the circuit that you'll be working on. If not, drill a hole down through the floor into the basement or crawlspace. Then continue the run to the circuit breaker panel. Leave about six feet of wire sticking through the hole by the dishwasher. This will allow the dishwasher to be pulled out during servicing. Take a piece of duct tape and tape the wire to the floor for now so that it doesn't slip down the hole that you just drilled.
Drilling Holes In Cabinets
Before you can install the drain hose, you'll need to drill a 1 ½” hole towards the back of the cabinet and as high as possible without hitting the sink. Ideally, the hose works best when it goes through the cabinet at a height above the dishwasher tub. If the drain hose is too low, the water will siphon out of the tub and you'll have soapy dishes.
Installing and Connecting the Drain Hose
After the hole is drilled using a paddle bit, insert the hose through the hole and attach it to the dishwasher drain fitting on your sink drain. If yours is not equipped with this, you'll need to install one. Another possibility is that you have a garbage disposal. It comes equipped with a fitting, but there is a knockout in the center of the fitting hole that must be removed before installing the drain hose. Knock it out with a round punch and a hammer. Now slide the hose clamp over the drain hose. Slide the drain hose over the fitting and tighten the clamp.
Connect the Water Line
To install the water line to the dishwasher, you'll need a water tap with a shutoff valve. There are easy tap valve that connect over existing water lines that bolt down around the line and with a sharp, pointy bolt, it pierces the waterline to feed the dishwasher. Install this if it is needed and connect one end of the water line to the tap valve and the other end to the dishwasher's water valve. You'll likely need to add a brass fitting to the water valve to accommodate the ¼” water line's nut. Use liquid thread compound to lube the threads being installed into the water valve.
Wire the Dishwasher
To access the wiring junction box, use a nut driver or screw driver to remove the two base plate screws on the front of the dishwasher. On the right side of the unit will be a metal junction box. Usually, you'll need a nut driver to remove the cover bolt. Once removed, you'll see a ½” hole where the wire will be installed using a Romex connector. Stick six inches of wire into the connector and tighten. Insert the wire into the hole and install the lock nut to hold the connector. Strip the wires and connect the black to black, white to white, and bare copper wire to the ground screw.
Install the Dishwasher into the Cabinet
Gently slide the dishwasher into place while carefully watching the water line, drain hose, and electrical wire. Once in place, level and plumb the dishwasher, leaving the same amount of room on both sides of the unit. Adjust the front and back legs until the dishwasher has about ½” to ¾” gap below the counter top. On the top of the dishwasher are two brackets. Using the two mounting screws provided, install them through the bracket holes into the bottom of the counter top. Be sure that the bracket is not sticking out from the counter.
Check the Installation
The next step is to check all of the connections. First, turn on the water and make sure that there are no leaks. Next, turn on the circuit breaker feeding the dishwasher and press start on one of the cycles on the dishwasher. Allow the unit to fill with water and start washing. Now press the cancel button and the unit will drain. Be sure that there are no leaks under the sink or under the dishwasher.
Install the Base Covers
Once you're convinced that everything is working properly, install the base plates to the dishwasher. They have elongated slots to allow the cover plates to reach the floor. Once these are installed, your dishwasher is now a fixture in your home. the best part is, no more dishes piled up in the sink!
Shop and Compare Dishwashers
- Always disconnect the circuit that you will be working on.
- If removing an old dishwasher, have a bucket ready to catch the excess water from the drain hose when you disconnect it. Also have a towel ready to mop up excess water from the water line connection.
- Use Teflon thread compound on water line threads to avoid leaks.
- Use a level to make sure that the dishwasher is level and plumb so that water doesn't run out of the door.
- Always check the water and drain connection points when you first turn on the dishwasher. Look to see there are no leaks before installing the base plate.
What You Need
- Phillpis and Straight Blade Screwdrivers
- Nut Drivers
- Wire Nuts
- Water Line
- Romex Wire (12-2 NM Wire with Ground)
- Wire Strippers
- Romex Connectors
- Razor Knife
- Liquid Teflon
- Various Sized Crescent Wrenches