Your Step-By-Step Guide To Installing A New Dishwasher

how to install a dishwasher

Installing a new dishwasher yourself is more cost-efficient than hiring a handyman. This is something you can do yourself with a few tools you probably already own, but it is important to know what you are getting into before getting started. Here is what you need to know how to install a dishwasher.

Will The New Dishwasher Fit?

a new dishwasher

Most dishwashers have a width of 24,” but you can find some 18” models. If you are replacing an old dishwasher, you should already know the width of the cabinet in which you are mounting your new dishwasher. Otherwise, carefully measure the width, height, and depth of the opening.

To adjust the height, you have to remove the service panel located under the door of the appliance. There should be hidden screws directly under the door that you can remove before taking the service panel off.

You will find two leveling legs behind the service panel, and two leveling legs in the back of the appliance. Adjust them with a wrench to the desired height.

Adjusting the depth of a dishwasher isn’t possible. So check the specs of the new appliance to make sure it will align with your kitchen cabinets.

Make sure you will have enough clearance to open the door of the appliance and load dishes.

Removing Your Old Dishwasher

guy removing his old dishwasher

Turn the electricity off at the breaker and shut off the water valve located under your sink before disconnecting your old dishwasher. You will need to remove the service panel under the door of the appliance.

Once the panel is out, disconnect the electrical wiring, the water supply line, and the drain line. Use a wrench to loosen the bolt that keeps the wires in place, and a screwdriver to loosen the hose clamps securing the water supply and drain lines to the dishwasher. Get the electrical wires and tubing out of the way.

Remove the screws that secure the old dishwasher to the kitchen counter.

Lower the front leveling legs of the dishwasher with a wrench. You can skip this step if the old dishwasher isn’t mounted flush under a kitchen counter.

Work with Care

secure your floor

Place some newspapers or an old towel on the floor to prevent scratching and damages to your kitchen floor. You will have to pull the dishwasher out of the cabinet. If the dishwasher was sitting on the subfloor, lift it a little to clear the flooring.

It is best to get some help for this step since a dishwasher can weigh 150 pounds or more.

You can either take your old dishwasher to a local recycling center or contact local scrappers to get rid of the appliance instead of throwing it away.

Inspect the electrical wiring, water supply line, and drain line before installing the new dishwasher. Look for signs of rust and corrosion. Now is the perfect time to replace damaged wires or tubing before installing a new dishwasher.

How To Install a Dishwasher

check the water tubing

If you are installing your first dishwasher, you won’t be able to connect it existing water supply and drain lines or to existing wires.

If you are installing new wires and tubing, measure the depth of the cabinet opening since these wires and tubing will be connected to the front of the appliance and run back to the wall.

Electrical Connection

secure the outlet

Some dishwashers have a standard electrical cord and can plug in an outlet. Choosing one of these appliances would be more convenient if you have a nearby electrical outlet you can use or can hire an electrician to install an outlet under the kitchen cabinet.

Some dishwashers require a dedicated line connected to a circuit breaker panel. It is best to hire an electrician to install one of these lines.

Water Supply Line

dishwasher connector

The water supply line is a hose or tubing that runs from the water supply valve located under your sink to the appliance. You can purchase a dishwasher connector kit that includes the hose or tubing and fitting for the dishwasher if your new appliance didn’t come with these accessories.

Drain Line


Connect the drain line of the dishwasher to the garbage disposal or to the sink drain depending on what is more convenient. Check local plumbing codes to find out if you need to use an air gap fitting or a high loop.

Be sure to prevent suction in the drain line because it could cause dirty water to go back in the dishwasher. A drain line without proper venting is a sanitary risk and wouldn’t meet building code standards.

Your local building code will probably require you to use the air gap fitting method. You will need to install two fittings under your sink or countertop, and an air gap fitting on top of the sink or counter. This fitting will let fresh air into the drain line to prevent suction. Sinks usually have mounting holes for these fittings.

If your local building code allows the high loop method, all you have to do is loop the drain line as high as possible under the sink.

If you have a doubt about installing the drain line, hire a plumber. It is best not to take any chances with this step since a poorly-installed drain line could become a sanitary risk.

Installing Your New Dishwasher

installing the new dishwasher

Here is how to install a new dishwasher once you have all the connections figured out. Turn the electricity and water off for safety, and protect your kitchen floor with newspaper to prevent scratches.

Look for the screws located under the door of your new dishwasher. Remove them to open the service panel of the appliance.

Measure the height of the opening and adjust the leveling legs of the dishwasher with a wrench as needed. Use a level to make sure the height of the legs is even. You will also need to adjust the leveling legs located in the back of the appliance.

Connect The Drain Line

Start by connecting the drain line of the new dishwasher. The draining pump should be under the door of the appliance. Use a hose clamp to secure the connection and pliers to tighten the hose clamp.

You will find two paths under your dishwasher designed to house the electrical wire and the drain line. Insert the drain line in one of these openings and connect it to the air gap fitting under your sink or kitchen counter.

If your local building code allows high loop method, loop the drain line as high as possible under the sink and connect it to the garbage disposal or sink drain. Secure this connection with a hose clamp and pliers.

Connect The Water Supply Line

You will need to run a hose or tubing between the water supply valve under your sink and the water inlet valve located under the door of your dishwasher.

Use hose clamps and pliers to secure the connection to the water supply valve under your sink. You will need to tighten a nut to secure the connection to the inlet valve on your new dishwasher.

Plugging The Dishwasher In

You can plug the new dishwasher in a wall outlet if you purchased a model with a traditional electrical cord. Otherwise, you will have to locate the junction box under the appliance.

Follow these steps to plug in your new dishwasher:

  • Use a pair of wire strippers to remove insulation and expose the end of the wires.
  • Remove the cover of the junction box.
  • Look for the hole on the side of the junction box and insert the wires in it.
  • You should be able to secure the wires by tightening a nut on the side of the junction box.
  • Use wire nuts to connect each wire to the corresponding wire coming out of the junction box. All you have to do is match colors.
  • Put the junction cover back on.

Slide The Dishwasher In Its Cabinet


slide the new dishwasher in it's cabinet

Make sure the electrical wires and drain line run through the clear paths located under the appliance. Push the dishwasher back inside of the cabinet, and attach it to the countertop with screws and mounting brackets.

Use a level to make sure the leveling legs are even on each side and adjust them if needed.

Turn the electricity and water valve back on. You should test the dishwasher to see if there are any leaks before putting the service panel back on.

You should have a better idea of how to install a dishwasher after reading these instructions. Make sure you have all the necessary tools before getting started, measure the cabinet carefully, and check the owner’s manual that came with your new dishwasher to locate different parts such as the draining pump or the junction box.

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