There is good news for enthusiast beginners when it comes to how to install a dishwasher. Both older and modern energy-efficient models all have the same three basic connections. All that you will need to get familiar with is the drain line, the water supply, and the electrical hookup. The even greater news is that you can take care of this job yourself if you are moving into a house that has a dishwasher and you’re simply replacing that unit. All you have to do is to attach the old and new connections to the same lines.

A new installation is slightly more difficult. Nonetheless, this step-by-step guide on how to install a dishwasher should make everything go smoothly.

Step 1. Set up Water Supply

The most challenging part of installing the dishwasher will be running the water supply. Carefully and slowly begin to uncoil the copper tubing. Stop the moment you have enough to go from the water supply to the unit. Before cutting the tubing, leave extra copper spare. This way, the unit can slide in and out of the bay in case a repair is needed. With a pair of tubing cutters, cut the line. Afterwards, insert the tube bending spring where the tube connects to the hot water valve.

Place a compression nut and ferrule over the end near the valve. The nut can be hand-tightened on that water valve. Then use a wrench to turn one-quarter turn more.

Step 2. Position Electric & Water Lines

Locate the front-to-back paths under the dishwasher. These are keeping copper tubing separated from electrical wiring as they run from back to the front of the dishwasher. Measure the distances so they can reach the side of the unit. Transfer these two measurements to the floor where the dishwasher will be inside the bay.

Remember which side leads to electrical wiring and which goes to the water hookup. Shape the copper pipe with an outside bending spring so it can wrap down the side of the cabinet. Start twisting the electrical wire so it follows the correct path too. Use duct tape to secure both lines to the floor.

Step 3. Connect Water Supply

table with kitchen sketch, red tap, flexible hoses for water supply

Place a tarp on the floor to protect the dishwasher from scratching, then tip it over on its back. Take off the cover panel that is located at the bottom of the dishwasher. Place Teflon tape, aka plumbers tape, around the threads of the water inlet.

Hand screw the brass elbow to the inlet, tighten with an adjustable wrench. These are the hardest parts of how to install a dishwasher, so take your time early on. Bring the unit up and push it near the opening of the bay. Visually check that the electrical and water lines are aligned properly.

Begin feeding the drain line from the dishwasher through the hole in the cabinet to the water supply. As the drain line is moving into place, slowly slide the dishwasher into the bay at the same time.

Step 4. Connect Electrical Wiring

One important tip on how to install a dishwasher is to make sure the power is off before making the electrical connection. Cover the ends of the exposed wires with a cable clamp. Make sure the new elements are covering the sheathing that keeps the wires together.

Seal the clamping bracket with a screwdriver. Search for a nut on the cable camp that resembles the shape of a star. Unscrew the bolt. Through that hole, bring wires and threaded end to the same side of the junction box of the dishwasher. Fasten the clamp nut with your hands from inside the box. Afterwards, proceed to secure the same nut with a screwdriver.

Begin lining up the same colors of wiring and tighten them all together with the wire nuts. Stuff all the dishwasher wires into the box, cover with a metal cover plate, and screw the metal plate to the box.

Step 5. Attach the Water Drain

The hardest parts of how to install a dishwasher are behind us. Now we need to secure the unit in place. Put a hose clamp over the end of the drain line. Push that open end of the hose on the sink drain inlet. It should be branching off the drain tailpipe or near the side of the garbage disposal. Be careful that you do not kink the line while installing.

Avoid letting the hose wrap around the spray-hose line. Slide hose clamp over the connection. Use a screwdriver to tighten the screw until the hose is secured in place.

Step 6. Attach Hose Strapping

Take some plumber’s strapping and wrap it around the drain line. Before securing the drain line and strapping to the back of the cabinet, make sure to create an arc. It has to be slightly higher than the drain inlet. Using the screwdriver, secure the strapping to the wall.

Step 7. Move Dishwasher in Place

Reach your hands to the front of the dishwasher. Start adjusting the feet until all the mounting brackets are flush with the underside of the counter. Next, open up the door of the dishwasher. Afterwards, adjust those feet again until the unit is level under the counter from side to side.

Step 8. Secure Dishwasher in Place

Now that the dishwasher is in position and level, it is time to fasten it to the underside of the counter with screws and mounting brackets. Secure the cover panel that goes at the base of the dishwasher. If the unit appears uneven, go back and adjust the feet again and then secure in place.

Step 9. Check for Leaks

inside dishwasher full of clean dishes

Turn the power on, turn the water supply on, and look for leaks. Search closely for any leaks near those water connections over the next few hours. If water drips from those connections, tighten the compression fitting slightly. Once the leaks stop, give the dishwasher a test-run.


These simple steps on how to install a dishwasher work for the seasoned repairman or the enthusiastic beginner. Work through the steps slowly so there will be no need to redo a bad job. The unit should be up and running in just a short matter of time. If you have experienced any issues along the way and have found simple solutions, share your experience here for further guidance.

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