While the installation of a new dishwasher often seems like something a professional repair technician should handle, the process is easier than you might think. In fact, provided you follow a few important rules, there’s no reason you can’t install (or reinstall) your dishwasher on your own. Since dishwashers can differ from model to model, following the owner’s manual, or the installation instructions, that came with the appliance is always recommended. But to help augment those instructions, here are some general directions you can follow to get the dishwasher up and running in time to clean the dirty dishes from tonight’s dinner.
What you need to know and do before installing the dishwasher
- If you’re replacing an existing dishwasher, confirm that the water and power supply connections are accessible and in the proper locations as indicated in the installation manual.
- If this is a first-time installation, you will need to drill access holes in the cabinet for the electrical wiring, water supply line, and drain hose. You should refer to the installation manual for the proper hole size and location, but keep in mind the cabinet hole for the supply line and drain hose should allow access to the area below the kitchen sink.
- For wood countertops, we recommend applying moisture barrier tape to the underside of the countertop along the front edge of the counter.
- Most dishwashers require 120 volts of alternating current running at 60 Hertz to operate. A dedicated circuit is recommended.
- The dishwasher can be powered through direct-wiring (be sure to only use copper wiring for this) or with an UL-listed power cord.
- A dishwasher water supply line should be connected to the home’s hot water supply line in compliance with local codes and ordinances.
- Confirm the power supply circuit has been shut off and the water supply valve is closed before installing or reinstalling the dishwasher.
Getting the dishwasher ready for installation
Have an assistant help you to remove the dishwasher from the shipping box (if applicable), then tip the appliance back and rest the rear panel on a large piece of cardboard to protect the flooring. Unthread the screws or rotate the fasteners securing the lower access panel or panels, then set the panel(s) aside along with any insulation.
Measure the height of the cabinet opening from the underside of the countertop to the floor. If the installation manual has a height chart, you can use this information to determine how far you should extend the dishwasher’s leveling legs from the base. As a general guideline, the height of the appliance should be about a quarter-inch less than the cabinet opening. If the cabinet opening is less than 34”, you can often remove the rear wheels, or the rear legs and spacers, to gain more clearance.
If not already present, you will need to attach a 90° elbow fitting to the water inlet valve inlet port. Confirm a rubber washer in present in the elbow fitting before threading it onto the valve port. If applicable, attach the drain hose to the appliance’s drain pump and secure with a clamp.
If the dishwasher is to be powered using a power cord (as opposed to direct-wiring), remove the terminal box cover and install a UL-listed metallic strain relief. Route the power cord through the strain relief. Secure the green grounding wire to the grounding screw in the terminal box, if applicable, or attach it to the green grounding wire using a wire nut. Any exposed grounding wire should be insulated with electrical tape. Next, join the two black wires together using a wire nut to hold them together. Do the same for the two white wires. Be aware that no more than two wire connecters plus the one grounding connecter should be in the terminal box. Tighten the strain relief screws to secure the cord, then replace and secure the terminal box cover. Making sure the power cord does not come in contact with the dishwasher’s circulation or drain pump motors, or the lower portion of the tub, route the cord out the rear of the appliance, but don’t plug it in at this time.
If the door handle did not come installed on the new appliance, you can now align it on the mounting studs and tighten the set screws to secure it.
Directions for installing the dishwasher
- Return the dishwasher to its upright position, keeping it on the cardboard.
- Route the drain hose out through the rear of the dishwasher and through the hole in the cabinet.
- If applicable, route the power cord through the appropriate cabinet hole.
- Route the water supply line out though the cabinet hole so it will be accessible when you push the dishwasher into the cabinet.
- Gently push the dishwasher into the cabinet space. Be sure to avoid bunching up the insulation blanket if applicable to your model,.
- Remove the cardboard from under the dishwasher and adjust the front leveling legs, if necessary, to level the appliance.
- Usually, the mounting brackets can be used to secure the dishwasher to the sides of the cabinet or the countertop. Keep in mind, the dishwasher should be side-mounted if there is more than a quarter-inch gap between the door and the underside of the countertop, or the countertop is made of granite or another dense material that won’t accept screws. You may need to purchase a side-mounting kit in order to do this. Depending on the model, you may need to align the brackets in the dishwasher frame and bend the retaining tabs to hold them in place. Side-mounting may require you to shorten the brackets by breaking off the end of the brackets at the appropriate score lines.
- Drill pilot holes into the cabinet or countertop, if necessary, to avoid splitting the wood, then thread the screws to secure the mounting brackets. When top-mounting, confirm the top of the door does not come into contact with the screws.
- If the dishwasher is being powered through direct-wiring (instead of a power cord), first confirm the power line is secured in a strain relief. Remove the terminal box cover, feed the power supply line and strain relief into the terminal box, then thread the strain relief nut to secure. Join the black wires to the black wires and the white wires to the white wires using wire nuts. The green grounding wire may be connected to a grounding wire found in the terminal box (using a wire nut) or to a grounding screw. Replace and secure the terminal box cover.
- Connect the water supply line to the elbow fitting attached to the dishwasher’s water inlet valve.
- Connect the drain hose to the garbage disposal (if available). Otherwise, it can be connected to a sink drain pipe using a clamp or an air gap. Keep in mind, you may need to trim the end of the drain hose where indicated to modify the connection so it will fit onto the appropriate port. Be aware: if the disposal has not been used in conjunction with a dishwasher before, you will probably need to knock out the disposal’s drain tube plug using a screwdriver and hammer.
- The drain hose should be looped above the connection point and held in place with wire or another retainer to prevent water from siphoning back into the dishwasher. The connection point itself should be at least twenty inches from the floor of the kitchen. If the connection point is less than twenty inches (or when prevented by code), an air gap will need to be used.
- If applicable, plug the power cord in or restore the power supply.
- Turn the water supply on.
- Run the dishwasher to confirm the tub is filling properly and there are no leaks.
- Complete the installation by replacing the insulation as required and securing the lower access panel or panels.
Find the right dishwasher parts with Repair Clinic
Repair Clinic stocks all the appliance parts you need to install, reinstall, maintain, or repair your dishwasher: mounting brackets, water supply lines, drain hoses, leveling legs, water inlet valves, drain pumps, spray arms, dishracks, and much more. Just enter the full model number of your dishwasher in the Repair Clinic search bar to see a complete list of compatible parts. You can use the part category and part title filters to narrow that list down to identify the specific part you want. Repair Clinic stocks parts for all the top brand dishwashers including Bosch, KitchenAid, Kenmore, Maytag, Samsung, GE, Frigidaire, LG, and Whirlpool, but you’ll want to make sure you’re purchasing the exact part that fits your model.